U.S. support to South Vietnam before Gulf of Tonkin
After the North Vietnamese had made a firm decision to commit to a military conquest of the South, a buildup phase began, between the 1959 North Vietnamese decision and the Gulf of Tonkin incident, which led to major U.S. escalation. The Communists saw this as a second phase of their revolution, substituting the U.S. for the French.
To put the situation in context, remember that North and South Vietnam were artificial constructs of the 1954 Geneva agreements. While there had been several regions of Vietnam, when roughly a million northerners, of different religion and ethnicity than in the south, migrated into a population of four to five million, there were identity conflicts. Communism has been called a secular religion, and both the military commanders and the North Vietnamese government officials responsible for psychological warfare and prisoner-of-war indoctrination were part of a dau tranh system that drew no division between state and ideology, much as Islamist theory draws no distinction between state and theology. Vietnamese Communism, for its converts, was an organizing belief system that had no equivalent in the South. At best, the southern leadership intended to have a prosperous nation, although leaders were all too often focused on personal prosperity. Their Communist counterparts, however, had a mission of conversion by the sword — or the AK-47 assault rifle.
Between the 1954 Geneva accords and 1956, the two countries were still forming; the influence of major powers, especially France and the United States, and to a lesser extent China and the Soviet Union, were as much an influence as any internal matters. There is little question that in 1957-1958, there was a definite early guerrilla movement against the Diem government, involving individual assassinations, expropriations, recruiting, shadow government, and other things characteristic of Mao's Phase I. The actual insurgents, however, were primarily native to the south or had been there for some time. While there was clearly communications and perhaps arms supply from the north, there is little evidence of any Northern units in the South, although organizers may well have infiltrated.
It can be established that there was endemic insurgency in South Vietnam throughout the period 1954-1960. It can also be established-but less surely- that the Diem regime alienated itself from one after another of those elements within Vietnam which might have offered it political support, and was grievously at fault in its rural programs. That these conditions engendered animosity toward the GVN seems almost certain, and they could have led to a major resistance movement even without North Vietnamese help.
There is little doubt that there was some kind of Viet Minh-derived "stay behind" organization between 1954 and 1960, but it is unclear that they were directed to take over action until 1957 or later. Before that, they were unquestionably recruiting and building infrastructure, a basic first step in a Maoist protracted war mode.
While the visible guerrilla incidents increased gradually, the key policy decisions by the North were made in 1959. Early in this period, there was a greater degree of conflict in Laos than in South Vietnam. U.S. combat involvement was, at first, greater in Laos, but the activity of advisors, and increasingly U.S. direct support to South Vietnamese soldiers, increased, under U.S. military authority, in late 1959 and early 1960. Communications intercepts in 1959, for example, confirmed the start of the Ho Chi Minh trail and other preparation for large-scale fighting.
North Vietnam committed in, May 1959, to war in the South; this was confirmed by communications intelligence. Diem, well before that point, had constantly pushed a generic anticommunism, but how much of this was considered a real threat, and how much a nucleus around which he justified his controls, is less clear. Those controls, and the shutdown of most indigenous opposition by 1959, was clearly alienating the Diem government from significant parts of the Southern population, was massively mismanaging rural reforms and overemphasizing the power base in the cities, and might have had an independent rebellion. North Vietnam, however, clearly began to exploit that alienation. The U.S., however, did not recognize a significant threat, even with such information as intelligence on the formation of the logistics structure for infiltration. The presentation of hard evidence — communications intelligence about the organization building the Ho Chi Minh trail — Hanoi's involvement in the developing strife became evident. Not until 1960, however, did the U.S. recognize both Diem was in danger, that the Diem structure was inadequate to deal with the problems, and present the first "Counterinsurgency Plan for Vietnam (CIP)"
Republic of Vietnam strategy
Quite separate from its internal problems, South Vietnam faced an unusual military challenge. On the one hand, there was a threat of a conventional, cross-border strike from the North, reminiscent of the Korean War. In the fifties, the U.S. advisors focused on building a "mirror image" of the U.S. Army, designed to meet and defeat a conventional invasion. 
Diem (and his successors) were primarily interested in using the ARVN as a device to secure power, rather than as a tool to unify the nation and defeat its enemies. Province and District Chiefs in the rural areas were usually military officers, but reported to political leadership in Saigon rather than the military operational chain of command. The 1960 "Counterinsurgency Plan for Vietnam (CIP)" from the U.S. MAAG was a proposal to change what appeared to be a dysfunctional structure.  Further analysis showed the situation was not only jockeying for power, but also reflected that the province chief indeed had security authority that could conflict with that of tactical military operations in progress, but also had responsibility for the civil administration of the province. That civil administration function became more and more intertwined, starting in 1964 and with acceleration in 1966, of the "other war" of rural development.
An issue that remains unclear is whether or not any of the post-Diem governments seriously explored a neutralist solution through direct negotiations with Hanoi, which would have been against U.S. policy. Contemporary intelligence analyses discount such negotiations, although they remained an undercurrent; Robert McNamara's 1999 book says that "Big" Minh, the leader of the coup that actually overthrew Diem, was actively exploring such an approach without informing the U.S.
Throughout this period, there clearly was a disconnect about South Vietnamese motivations. Analyses by the Bureau of Intelligence and Research (INR) of the U.S. Department of State define the political problems from a viewpoint different from that of the military. They described the immediate post-coup government, controlled by the popular "Big" Minh with Nguyen Ngoc Tho as figurehead Prime Minister, unable to get control, and the Khanh-led military junta that replaced him simply being a period of instability.
INR saw the priority during this period as more a matter of establishing a viable, sustainable political structure for South Vietnam, rather than radically improving the short-term security situation. It saw the Minh-Tho government as enjoying an initial period of popular support as it removed some of the most disliked aspects of the Diem government. During this time, the increase in VC attacks was largely coincidental; they were resulting from the VC having reached a level of offensive capability rather than capitalizing on the overthrow of Diem.
Contrary to the INR analysis, Douglas Pike said that there was a substantial defection from the NLF after the overthrow of Diem, especially among Cao Dai that had considered themselves as especially persecuted by Diem. Pike believed that a portion of the NLF was variously anti-Diem, or simply in search of political power, rather than Communist. When this part left, the NLF came much more under Hanoi's control.
During this period, INR observed, in a December 23 paper, the U.S. needed to reexamine its strategy focused on the Strategic Hamlet Program, since it was getting much more accurate — if pessimistic — from the new government than it had from Diem. Secretary McNamara, however, testified to the House Armed Service Committee, on December 27, that only a maximum effort of American power could salvage the situation. Two days later, the Minh-Tho government was overthrown.
INR looked pessimistically at Khanh, who claimed that Minh had been making overtures to Hanoi for a neutralist settlement. It was the contemporary assessment of INR that Minh had been making no such overtures, although this is contradicted by Secretary McNamara's 1999 book.
Whether or not Khanh was right about Minh's plan, INR judged Minh as motivated primarily by personal ambition. Where Minh had tried to form a government of technicians, Khanh, admittedly with U.S. urging, brought in political elements, which quickly led to factionalism not present under Minh's period of good will. INR saw Khanh as having a contradictory policy in terms of U.S. goals: while he did increase security, he did so by means judged counterproductive in broadening the political base of the government.
INR considered new student demonstrations, in April 1964, as the first warning of a new wave of protest, which became more manifest in August. Those demonstrations contained anti-American messages, but INR was uncertain if they represented true anti-Americanism, or simply opposition to American support of Khanh. As opposed to Diem's catastrophic handling of the Buddhist crisis, Khanh responded with moderation, and, on August 28, INR concluded he was, in fact, improving the political situation. Evidence cited including the dissolution, in the next two weeks, of Minh's military triumvirate and Minh's election as chairman of a new Provisional Steering Committee, as well as release of some jailed generals that had supported Minh. INR suggested that Khanh may have caused the unrest by supporting the genuinely popular Khanh. Khanh, however, promptly sent Minh to exile in Thailand.
Note that Minh was exiled within the same month as the Gulf of Tonkin incident, with its obvious ramifications of increased U.S. involvement.
The North had clearly defined political objectives, and a grand strategy, involving military, diplomatic, covert action and psychological operations to achieve those objectives. Whether or not one agreed with those objectives, there was a clear relationship between long-term goals and short-term actions. Its military first focused on guerrilla and raid warfare in the south (i.e., Mao's "Phase I"), simultaneously improving the air defences of the north. By the mid-sixties, they were operating in battalion and larger military formation that would remain in contact as long as the correlation of forces was to their advantage, and then retreat — Mao's "Phase II".
In the Viet Cong, and in the North Vietnam regular army (PAVN), every unit had political and military cadre to ensure dau tranh was carried out.
Guerrilla attacks increased in the early 1960s, at the same time as the new John F. Kennedy administration made Presidential decisions to increase its influence. Diem, as other powers were deciding their policies, was clearly facing disorganized attacks and internal political dissent. There were unquestioned conflicts between the government, dominated by minority Northern Catholics, and both the majority Buddhists and minorities such as the Montagnards, Cao Dai, and Hoa Hao. These conflicts were exploited, initially at the level of propaganda and recruiting, by stay-behind Viet Minh receiving orders from the North.
Diem,in early 1959, felt under attack and broadly reacted against all forms of opposition, which was presented as a "Communist Denunciation Campaign", as well as some significant and unwelcome rural resettlement, the latter to be distinguished from land reform.
Increased activity in Laos
In May, the North Vietnamese made the commitment to an armed overthrow of the South, creating the 559th Transportation Group, named after the creation date, to operate the land route that became known as the Ho Chi Minh Trail. Additional transportation groups were created for maritime supply to the South: Group 759 ran sea-based operations, while Group 959 supplied the Pathet Lao by land routes. . Group 959 also provided secure communications to the Pathet Lao. 
The Pathet Lao both were operating against the Laotian government, but also working with NVA Group 959 to supply the southern insurgency; much of the original Trail was in Laos, first supplying the Pathet Lao. Nevertheless. the Laotian government did not want it known that it was being assisted by the US in the Laotian Civil War against the Pathet Lao. U.S. military assistance could also be considered a violation of the Geneva agreement, although North Vietnam, and its suppliers, were equally in violation.
In July, CIA sent a unit from United States Army Special Forces, who arrived on CIA proprietary airline Air America, wearing civilian clothes and having no obvious US connection. These soldiers led Meo and Hmong tribesmen against Communist forces. The covert program was called Operation Hotfoot. At the US Embassy, BG John Heintges was called the head of the "Program Evaluation Office."
CIA directed Air America, in August 1959, to train two helicopter pilots. Originally, this was believed to be a short-term requirement, but "this would be the beginning of a major rotary-wing operation in Laos.
Escalation and response in the South
Cause and effect are unclear, but it is also accurate that the individual and small group actions, by the latter part of 1959, included raids by irregulars in battalion strength.
Vietnam was a significant part of the agenda of the U.S. Pacific commanders' conference in April. Lieutenant General Samuel T. Williams, chief of the U.S. Military Assistance Advisory Group, Vietnam (MAAG-V) cited the key concerns as:
- absence of a national plan for control of the situation
- no rotation of military units in the field
- the need for a central surveillance plan
- the proliferation of Ranger-type counterinsurgency units without central direction and without a civil-military context
- inadequate intelligence
- inadequate military communications
- lack of centralized direction of the war effort.
LTG Williams pointed to the dual chain of command of the ARVN, as distinct from the Civil Guard. The latter was commanded by the Department of the Interior, and controlled by province and district chiefs. This structure let the U.S. Operations Mission (USOM, the contemporary term for non-military foreign aid from the Agency for International Development financially aid the Guard, they were so dispersed that there could be no systematic advice, much less to the combination of Guard and Army. 
Under the authority of the commander of United States Pacific Command, it was ordered that MAAG-V assign advisors to the infantry regiment and special troops regiment level, who were not to participate directly in combat. advisers be provided down to infantry regiment and to artillery, armored, and separate Marine battalion level. This move would enable advisers to give on-the-spot advice and effectively assess the end result of the advisory effort. He also requested United States Army Special Forces (SF) mobile training teams (MTT) to assist in training ARVN units in counterinsurgency.
Structural barriers to effectiveness of RVN forces
When the MAAG was instructed to improve the effectiveness of the RVN, the most fundamental problem was that the Diem government had organized the military and paramilitary forces not for effectiveness, but for political control and patronage. The most obvious manifestation of Diem's goal was that there were two parallel organizations, the regular military under the Department of National Defense and the local defense forces under the Ministry of the Interior. Diem was the only person who could give orders to both.
Command and control
President Diem appointed the Secretary of State for National Defense and the Minister of the Interior. The Defense Secretary directed of General Staff chief and several special sub-departments. The General staff chief, in turn, commanded the Joint General Staff (JGS), which was both the top-level staff and the top of the military chain of command.
There were problems with the military structure, even before considering the paramilitary forces under the Interior Ministry. The JGS itself had conflicting components with no clear authority. For example, support for the Air Force came both from a Director of Air Technical Service and a Deputy Chief of Air Staff for Matériel. The Director was, in principle, under the Chief of Staff, but actually reported to the Director General of Administration, Budget, and Comptroller for fiscal matters).
Combat units also had conflicting chains of command. A division commander might receive orders both from the corps-level tactical commander who actually carried out the operational art role of corps commanders in most militaries, but also from the regional commander of the home base of the division — even if the division was operating in another area. The chiefs of branches of service (e.g., infantry, artillery), who in most armies were responsible only for preparation and training of personnel of their branch, and orders only before they were deployed, would give direct operational orders to units in the field.
Diem himself, who had no significant military background, could be the worst micromanager of all, getting on a radio in the garden of the Presidential Palace, and issuing orders to regiments, bypassing the Department of National Defense, Joint General Staff, operational commanders, and division commanders. He also consciously played subordinates against one another to avoid the formation of opposition; the Battle of Ap Bac was a defeat caused by a lack of unity of command, with conflicts between the military commander and province chief.
In fairness to Diem, Lyndon Johnson and his political advisors would do detailed air operations planning for attacks in the North, with no input from experienced air officers. Henry Kissinger, in the Mayaguez incident, got onto the tactical radio net and confused the local commanders with German-accented and obscure commands. Johnson and Kissinger did have had more military experience than Diem; Johnson had briefly worn a Navy uniform on an inspection trip before returning to Congress, and Kissinger lectured on politics at the end of WWII and the start of the Occupation, with a high status but an actual rank of Private, United States Army. Diem had never put on a uniform.
"The Department of National Defense and most of the central organizations and the ministerial services were located in downtown Saigon, while the General Staff (less air and navy elements) was inefficiently located in a series of company-size troop barracks on the edge of the city. The chief of the General Staff was thus removed several miles from the Department of National Defense. The navy and air staffs were also separately located in downtown Saigon. With such a physical layout, staff action and decision-making unduly delayed on even the simplest of matters.
"The over-all ministerial structure described above was originally set up by the French and slightly modified by presidential decree on 3 October 1957. Military Assistance Advisory Group, Vietnam, had proposed a different command structure which would have placed the ministry and the "general staff" in closer proximity both physically and in command relationship." Diem, however, made a practice of keeping individuals or small groups from having too much authority.
The chain of command of both the Civil Guard and Self-Defense Corps, went from the Ministry of the Interior to the province chiefs, district chiefs, and village councils. Even though the province chiefs and district chiefs were often military officers, ARVN units operating in a province or district could not give orders to these units. Instead, they had to pass a request through military channels to the Ministry of Defense in Saigon. If the officials there agreed, they would convey the request to their counterparts in the Ministry of the Interior, who would then send orders down its chain of command to the local units.
- Three corps headquarters and a special military district:
- Seven divisions of 10,450 men
- three infantry regiments
- artillery battalion
- mortar battalion
- engineer battalion
- company-size support elements
- Airborne group of five battalion groups
- four armored cavalry "regiments" (approximately the equivalent of a U.S. Army cavalry squadron)
- one squadron (U.S. troop) of M24 light tanks
- two squadrons of M8 self-propelled 75-mm. howitzers
- Eight independent artillery battalions with U.S. 105-mm, and 155-mm. pieces.
Local defense forces
Created by presidential decree in April 1955, and originally under the direct control of President Diem, with control passed to the Ministry of the Interior in September 1958, the Civil Guard was made up of wartime paramilitary veterans. Its major duty was to relieve the ARVN of static security missions, freeing it for mobile operations, with additional responsibility for local intelligence collection and counterintelligence. in 1956, had 68,000 men organized into organized into companies and platoons, the Civil Guard was represented by two to eight companies in each province. It had a centrally controlled reserve of eight mobile battalions of 500 men each, .
Operating on a local basis since 1955 and formally created in 1956, the Self-Defense corps was a village-level police organization, for protection against intimidation and subversion. It put units of 4-10 men into villages of 1,000 or more residents. In 1956, it had 48,000 non-uniformed troops armed with French weapons. The Self-Defense Corps, like the Civil Guard, was established to free regular forces from internal security duties by providing a police organization at village level to protect the population from subversion and intimidation. Units of four to ten men each were organized in villages of 1,000 or more inhabitants.
The Civil Guard and the Self-Defense Corps were poorly trained and ill-equipped to perform their missions, and by 1959 their numbers had declined to about 46,000 and 40,000, respectively.
As mentioned in the introduction to this section, the U.S. was urging the RVN to revise its parallel province/district command and military operations command structure; the Counterinsurgency Plan (CIP) was the first of several such proposals.
After the 180 day assignment of the Special Forces personnel in Laos, the name changed to Operation White Star, under COL Arthur "Bull" Simons.
Beginning of Phase II raids
On 25 January 1960, a Communist force of 300 to 500 men escalated with a direct raid on an ARVN base at Tay Ninh, killing 23 soldiers and taking large quantities of munitions. Four days later, a guerrilla group seized a town for several hours, and stole cash from a French citizen. These were still in the first Maoist stage, as raids rather than hit-and-run battles. Still, larger guerrilla forces broke lines of communications within areas of South Vietnam.
There was uncertainty, expressed by Bernard Fall and in a March U.S. intelligence assessment, that there were distinct plans to conduct larger-scale operations "under the flag of the People's Liberation Movement," which was identified as "red, with a blue star." It was uncertain if their intent was to continue to build bases in the Mekong Delta, or to isolate Saigon. The Pentagon Papers stated the guerrillas were establishing three options, of which they could exercise one or more;
- incite an ARVN revolt
- set up a popular front government in the lower Delta
- force the GVN into such repressive countermeasures that popular uprisings will follow.
Formation of the NLF
In December, the National Front for the Liberation of South Vietnam (NLF) formally declared its existence, although it did not hold its first full congress until 1962.
The NLF platform recognized some of the internal stresses under the Diem government, and put language in its platform to create autonomous regions in minority areas and for the abolition of the "U.S.-Diêm clique's present policy of ill-treatment and forced assimilation of the minority nationalities".  Such zones, with a sense of identity although certainly not political autonomy, did exist in the North. In the early 60s, NLF political organizers went to the Montagnard ares in the Central Highlands, and worked both to increase alienation from the GVN and directly recruit supporters.
Not surprisingly, with a change in U.S. administration, there were changes in policy, and also continuations of some existing activities. There were changes in outlook. Kennedy was unquestionably anti-Communist, but his administration did not treat it as the existential crusade that Eisenhower's secretary of state, John Foster Dulles, had waged.
Defense Secretary Robert S. McNamara (in office 1961-68) told President John F. Kennedy (in office 1961-63) in 1961 it was "absurd to think that a nation of 20 million people can be subverted by 15-20 thousand active guerrillas if the government and the people of that country do not wish to be subverted." McNamara, a manufacturing executive and expert in statistical management, had no background in guerrilla warfare or other than Western culture, and rejected advice from area specialists and military officers. He preferred to consult with his personal team, often called the "Whiz Kids"; his key foreign policy advisor was a law professor, John McNaughton, while economist Alain Enthoven was perhaps his closest colleague.
Still trying to resolve the problems of GVN conflicting command, a new reorganizational proposal, the "Geographically Phased Plan". The goal was to have a coherent national plan, which was, in 1962, to be expressed as the Strategic Hamlet Program.
Kennedy pushes for covert operations against the North
On January 28, 1961, shortly after his inauguration, John F. Kennedy told a National Security Council meeting that he wanted covert operations launched against North Vietnam, in retaliation for their equivalent actions in the South.. This is not argue that this was an inappropriate decision, but the existence of covert operations against the North, has to be understood in analyzing later events, especially the Gulf of Tonkin incident.
Even earlier, he issued National Security Action Memorandum (NSAM) 2, directing the military to prepare counterinsurgency forces, although not yet targeting the North. 
Kennedy discovered that little had progressed by mid-March, and issued National Security Action Memorandum (NSAM) 28, ordering the CIA respond to his desire to launch guerrilla operations against the North. Herb Weisshart, deputy chief of the Saigon CIA station, observed the actual CIA action plan was "very modest". Given the Presidential priority, Weisshart said it was modest because William Colby, then Saigon station chief, said it would consume too many resources needed in the South. He further directed, in April, a presidential task force to draft a "Program of Action for Vietnam".
In April, the Bay of Pigs invasion of Cuba, under the CIA, had failed, and Kennedy lost confidence in the CIA's paramilitary operations. Kennedy himself had some responsibility for largely cutting the Joint Chiefs of Staff out of operational planning. The JCS believed the operation was ill-advised, but, if it was to be done, American air support was absolutely essential. Kennedy, however, had made a number of changes to create plausible deniability, only allowing limited air strikes by CIA-sponsored pilots acting as Cuban dissidents. After it was learned that the main strike had left behind a few jet aircraft, he refused a followup strike; those aircraft savaged the poorly organized amphibious ships and their propeller-driven air support.
The U.S. Air Force, however, responded to NSAM 2 by creating, on April 14, 1961, the 4400th Combat Crew Training Squadron (CCTS), code named “Jungle Jim.” The unit, of about 350 men, had 16 C-47 transports, eight B-26 bombers, and eight T-28 trainers (equipped for ground attack), with an official of training indigenous air forces in counterinsurgency and conduct air operations. A volunteer unit, they would deploy in October, to begin FARM GATE missions.
The task force reported back in May, with a glum assessment of the situation in the South, and a wide-ranging but general plan of action, which becam NSAM 52. In June, Kennedy issued a set of NSAMs transferring paramilitary operations to the Department of Defense. . These transfers of responsibility should be considered not only in respect to the specific operations against the North, but in the level of covert military operation in the South in the upcoming months. This transfer also cut the experienced MG Edward Lansdale out of the process, as while he was an U.S. Air Force officer, the military saw him as belonging to CIA.
Also in May, the first U.S. signals intelligence unit, from the Army Security Agency under National Security Agency control, the unit, operating under the cover name of the 3rd Radio Research Unit. Organizationally, it provided support to MAAG-V, and trained ARVN personnel, the latter within security constraints. The general policy, throughout the war, was that ARVN intelligence personnel were not given access above the collateral SECRET (i.e., with no access to material with the additional special restrictions of "code word" communications intelligence (CCO or SI)".
Their principal initial responsibility was direction finding of Viet Cong radio transmitters, which they started doing from vehicles equipped with sensors. On December 22, 1961, an Army Security Agency soldier, SP4 James T. Davis, was killed in an ambush, the first American soldier to die in Vietnam.
Covert U.S. air support enters the South
More U.S. personnel, officially designated as advisors, arrived in the South and took an increasingly active, although covert, role. In October, a U.S. Air Force special operations squadron,, part of the 4400th CCTS deployed to SVN, officially in a role of advising and training. The aircraft were painted in South Vietnamese colors, and the aircrew wore uniforms without insignia and without U.S. ID. Sending military forces to South Vietnam was a violation of the Geneva Accords of 1954, and the U.S. wanted plausible deniability.
The deployment package consisted of 155 airmen, eight T-28s, and four modified and redesignated SC-47s and subsequently received B-26s. U.S. personnel flew combat as long as a VNAF person was aboard. FARMGATE stayed covert until after the Gulf of Tonkin incident.
Building the South Vietnamese Civil Irregular Defense Groups
Under the operational control of the Central Intelligence Agency, initial U.S. Army Special Forces involvement came in October, with the Rhade.  The Civilian Irregular Defense Groups (CIDG), were under Central Intelligence Agency operational control until July 1, 1963, when MACV took control. . Army documents refer to control by "CAS Saigon", a cover name for the CIA station. According to Kelly, the SF and CIA rationale for establishing the CIDG program with the Montagnards was that minority participation would broaden the GVN counterinsurgency program, but, more critically,
the Montagnards and other minority groups were prime targets for Communist propaganda, partly because of their dissatisfaction with the Vietnamese government, and it was important to prevent the Viet Cong from recruiting them and taking complete control of their large and strategic land holdings.
It was in mid-November when Kennedy decided to take on operational as well as advisory roles. Under U.S. a Military Assistance Advisory Group (MAAG), such as the senior U.S. military organization in Vietnam, is a support and advisory organization. A Military Assistance Command (MAC) is designed to carry out MAAG duties, but also to command combat troops. . There was considerable discussion about the reporting structure of this of the organization: a separate theater reporting to the National Command Authority or part of United States Pacific Command.
First Honolulu Conference
After meetings in Vietnam by GEN Taylor, the Secretaries of State and Defense issued a set of recommendations, on November 11.  Kennedy accepted all except the use of large U.S. combat forces.
McNamara held the first Honolulu Conference, at United States Pacific Command headquarters, with the Vietnam commanders present. He addressed short-term possibilities, urging concentration on stabilizing one province: "I'll guarantee it (the money and equipment) provided you have a plan based on one province. Take one place, sweep it and hold it in a plan." Or, put another way, let us demonstrate that in some place, in some way, we can achieve demonstrable gains. 
First U.S. direct support to an ARVN combat operation
On 11 December 1961 the United States aircraft carrier USNS Card docked in downtown Saigon with 82 U. S. Army H-21 helicopters and 400 men. organized into two Transportation Companies (Light Helicopter); Army aviation had not yet become a separate branch.
Twelve days later these helicopters were committed into the first airmobile combat action in Vietnam, Operation CHOPPER. It was the first time U.S. forces directly and overtly supported ARVN units in combat, although the American forces did not directly attack the guerrillas. Approximately 1,000 Vietnamese paratroopers were airlifted into a suspected Viet Cong headquarters complex about ten miles west of the Vietnamese capital, achieving tactical surprise and capturing a radio station. 
From the U.S. perspective, the Strategic Hamlet Program was the consensus approach to pacifying the countryside. There was a sense, however, that this was simply not a high priority for Diem, who considered his power base to be in the cities. The Communists, willing to fill a vacuum, became more and more active in rural areas where the GVN was invisible, irrelevant, or actively a hindrance.
Special Forces operations
In 1962, the U.S. Military Command–Vietnam (MACV) established Army Special Forces camps near villages. The Americans wanted a military presence there to block the infiltration of enemy forces from Laos, to provide a base for launching patrols into Laos to monitor the Ho Chi Minh Trail, and to serve as a western anchor for defense along the DMZ. These defended villages were not part of the Strategic Hamlet Program, but did provide examples that were relevant.
U.S. ground command structure established
U.S. command structures continued to emerge. On February 8, Paul D. Harkins, then Deputy Commanding General, U.S. Army Pacific, under Pacific Command, was promoted to general and assigned to command the new Military Assistance Command, Vietnam (MAC-V).
Military Assistance Command-Thailand was created on May 15, 1962, but reported to Harkins at MAC-V. In a departure from usual practice, the MAAG was retained as an organization subordinate to MAC-V, rather than being absorbed into it. The MAAG continued to command U.S. advisors and direct support to the ARVN. At first, MAC-V delegated control of U.S. combat units to the MAAG. While it was not an immediate concern, MAC-V never controlled all the Air Force and Navy units that would operate in Vietnam, but from outside its borders. These remained under the control of Pacific Command, or, in some cases, the Strategic Air Command.
No regular ARVN units were under the command of U.S. military commanders, although there were exceptions for irregular units under Special Forces. Indeed, there could be situations where, in a joint operation, U.S. combat troops were under a U.S. commander, while the ARVN units were under an ARVN officer with a U.S. advisor. Relationships in particular operations often were more a matter of personalities and politics rather than ideal command. U.S troops also did not report to ARVN officers; while many RVN officers had their post through political connections, others would have been outstanding commanders in any army.
At the same time, the U.S. was beginning to explore withdrawing forces. 
Intelligence support refines
The USMC 1st Composite Radio Company deployed, on January 2, 1962, to Pleiku, South Vietnam as Detachment One. After Davis' death in December, it became obvious to the Army Security Agency that thick jungle made tactical ground collection exceptionally dangerous, and direction-finding moved principally to aircraft platforms. See first-generation Army tactical SIGINT.
Additional allied support
In addition to the U.S. advisers, in August 1962, 30 Australian Army advisers was sent to Vietnam to operate within the United States military advisory system. As with most American advisors, their initial orders were to train, but not go on operations.
1963 was critical not only because the Diem government fell, but that the North, at the end of the year, chose a more aggressive military strategy.
Stability in the South, however, would not improve with increasing dissent, coup attempts, and a major coup. It remains unclear as to what extent the South Vietnamese were exploring solutions based a neutralist Vietnam, but this apparently existed at some level, without U.S. knowledge.
Organizations and personnel
Organizations and commands would change with time. In January, for example, Major General Don became Commander-in-Chief of the RVN armed forces, GEN William Westmoreland was named deputy to GEN Paul Harkins to replace him later. In a structural reorganization, the ARVN made the Saigon Special Region the III Corps tactical zone; the former III Corps for the Mekong Delta became IV Corps tactical zone
January 1963: Question of ARVN effectiveness
South Vietnamese forces, with U.S. advisors, took severe defeats at the Battle of Ap Bac in January,. This has been considered the trigger for an increasingly skeptical, although small, American press corps in Vietnam. and the Battle of Go Cong in September. Ap Bac was of particular political sensitivity, as John Paul Vann, a highly visible American officer, was the advisor, and the U.S. press took note of what he considered to be ARVN shortcomings.
While the Buddhist crisis and military coup that ended with the killing of Diem was an obvious major event, it was by no means the only event of the year. In keeping with the President's expressed desires, covert operations against the North were escalated. Of course, the assassination of Kennedy himself brought Lyndon Baines Johnson, with a different philosophy toward the war. Kennedy was an activist, but had a sense of unconventional warfare and geopolitics, and, as is seen in the documentary record, discussed policy development with a wide range of advisors, specifically including military leaders although he distrusted the Joint Chiefs of Staff.  He was attracted to officers that he saw as activist and unconventional, such as Edward Lansdale.
Johnson tended to view the situation from the standpoint of U.S. domestic policy, and did not want to render himself vulnerable to political criticism as the man who had "lost Vietnam".  Early after becoming president, as he told Bill Moyers, he had the "terrible feeling that something has grabbed me by the ankles and won't let go." His response was to send Robert McNamara to examine the situation and reassure him. McNamara, at this point as he had been with Kennedy, exuded a sense of logical control; he was not yet in the deep despair that led him to write, "...we were wrong, terribly wrong. We owe it to future generations to explain why."
"Johnson was a profoundly insecure man who craved and demanded affirmation." When the North Vietnamese did not respond as Johnson wanted, he took it personally, and may have made some judgments based on his emotional responses to Ho. He also spoke with a much smaller advisory circle than Kennedy, and excluded active military officers.
The Buddhist crisis begins
While there had been long-standing animosity between Diem and the Buddhists. April 1963. For unclear reasons, the central government ordered the provincial authorities to enforce a ban on the display of all religious flags. This ban had rarely been enforced, but, since the order went out shortly before the major festival, Vesek (informally called Buddha's Birthday), which fell on May 8, many Buddhists perceived this as a direct attack on their customs.
In May, a government paramilitary unit fired into demonstrators. As part of a wave of protests, a Buddhist monk immolated himself; photographs of his body, apparently seated calmly in the lotus position as he burned to death, drew worldwide attention. By early June, the government was negotiating with the Buddhists as it had never done, with Vice President Tho, a Buddhist, apparently being an effective negotiator in spite of Diem's brother and political advisor Ngô Đình Nhu's announcing "if the Buddhists want to have another barbecue, I will be glad to supply the gasoline".
May 1963 Honolulu conference; covert warfare a major issue
At the May 6 Honolulu conference, the decision was made to increase, as the President had been pushing, covert operations against the North. A detailed plan for covert operations, Pacific Command Operations Plan 34A (OPPLAN 34A) went to GEN Taylor, now Chairman of the Joint Chiefs of Staff, did not approve it until September 9. Shultz suggests the delay had three aspects:
- Washington was preoccupied with the Buddhist crisis
- MACV had no established covert operations force, so even if he approved a plan, there was no one to execute it
- Taylor, although a distinguished Airborne (paratroopers once being believed special operators) officer, disagreed with Kennedy's emphasis on covert operations, did not have the appropriate resources in the Department of Defense, and he did not believe it was a proper job for soldiers.
- Diem, fighting for survival, was not interested
It is unclear if Taylor did not believe covert operations should not be attempted at all, or if he regarded it as a CIA mission. If the latter, Kennedy would have been unlikely to support him, given the President's loss of confidence after the Bay of Pigs fiasco. 
Diem was overthrown and killed on November 1.
Secretary of State Rusk counseled a delay in meeting with the coup leadership, which had started calling itself the "Revolutionary Committee", to avoid appearance of it being a U.S. coup. Apparently unknown to the U.S., the plotters had negotiated, beforehand, with vice-president Nguyen Ngoc Tho, who, himself a Buddhist, had been the chief government negotiator in the Buddhist crisis. In the immediate followup of the coup, Diem's cabinet were told to resign, and there were no reprisals. Tho, however, was negotiating with the committee, especially the most powerful general, Duong Van Minh knowing that the military leaders wanted him in the new civilian government.
Generals Tran Van Don, chief of staff, and Le Van Kim, his deputy, called at the Embassy on November 3.  Explaining that Minh was, as they spoke, with Tho, they said would be a two-tiered government structure with a military committee presided over by General Duong Van Minh overseeing a regular cabinet that would be mostly civilian with Tho as prime minister.
On the 4th, Lodge and Conein met with Lodge, Generals Minh and Don. Afterwards, Lodge reported, "Minh seemed tired and somewhat frazzled; obviously a good, well-intentioned man. Will he be strong enough to get on top of things?" The new government was announced on the 6th: General Minh was Chairman, Don and Dinh were Deputy Chairmen, and nine other generals, including Kim, Khiem, "little" Minh, Chieu, and Thieu were members. General Nguyen Khanh, the commander of II Corps tactical zone in central Vietnam, was not in the government.
After two assassinations
Kennedy and Diem both died in November 1963. Lyndon Johnson became the new President of the United States. Johnson was far more focused on domestic politics than the international activist, Kennedy. Some of the Kennedy team left quickly, while others, sometimes surprisingly given extremely different personalities, stayed on; the formal and logical Robert McNamara quickly bonded with the emotional and deal-making Johnson.
McNamara was insistent that a rational enemy would not accept the massive casualties that indeed were inflicted on the Communists. The enemy, however, was willing to accept those casualties.  McNamara was insistent that the enemy would comply with his concepts of cost-effectiveness, of which Ho and Giap were unaware. They were, however, quite familiar with attritional strategies. While they were not politically Maoist, they were also well versed in Mao's concepts of protracted war (see insurgency).
Three things concerned the U.S.:
- How stable was the new government? Was the presence of an empowered Tho a threat to Minh and the other generals?
- The economy was in tatters, partially due to the suspension of aid as a lever on Diem
- Statistical indicators showed that VC attacks were increased in comparison with the first half of the year, and MACV was concerned that units involved in the coup were not getting back to the field.
Johnson approval of covert operations
OPPLAN 34A was finalized around December 20, under joint MACV-CIA leadership; the subsequent MACV-SOG organization had not yet been created. There were five broad categories, to be planned in three periods of 4 months each,over a year:
- Clandestine human-source and signals intelligence collection from locations in the north
- Psychological operations against the north to increase tension and division; Colby had already started such operations
- Paramilitary operations,such as raids and sabotage against facilities that were significant to the admittedly weak economy, and stronger security, of North Vietnam
- Encouraging the development of an underground resistance movement
- Selected raids as well as reconnaissance to direct air strikes, with more of a tactical goal than the economic and security actions of category
Lyndon Johnson agreed with the idea, but was cautious. He created an interdepartmental review committee, under MG Victor Krulak, on December 21, to select the least risky operations on December 21, which delivered a report on January 2, 1964, for the first operational phase to begin on February 1. It was hardly an expression of the motto of David Stirling, founder of Britain's legendary Special Air Service: "Who dares, wins."
North Vietnam decides on escalation
INR determined that the North Vietnamese had, in December, adopted a more aggressive stance toward the South, which was in keeping with Chinese policy. This tended to be confirmed with more military action and less desire to negotiate in February and March 1964 Duiker saw the political dynamics putting Le Duan in charge and Ho becoming a figurehead. 
COL Bui Tin led a reconnaissance mission of specialists reporting directly to the Politburo, who said, in an 1981 interview with Stanley Karnow, that he saw the only choice was escalation including the use of conventional troops, capitalizing on the unrest and inefficiency from the series of coups in the South. The Politburo ordered infrastructure improvements to start in 1964.
late 1963 to 1964 (before Gulf of Tonkin Incident)
In February and March 1964, confirming the December decision, there was more emphasis on military action and less attention to negotiation.  As opposed to many analysts who believed the North was simply unaware of McNamara's "signaling"; INR thought that the North was concerned of undefined U.S. action on the North and sought Chinese support. If INR's analysis is correct, the very signals mentioned in the March 1965 McNaughton memo, which was very much concerned with Chinese involvement, may have brought it closer.
There were numerous ARVN and VC raids, of battalion size, for which only RVN losses or body count is available. They took place roughly monthly. In the great casualty lists of a war, 100-300 casualties may not seem an immense number, but these have to be considered as happening at least once a month, with a population of perhaps 10 million. It was a grinding war of attrition, with no decision, as death and destruction ground along.
For example, on March 23, 1964, ARVN forces in Operation PHUONG HOANG 13-14/10, Dien Phong Sector, raids a VC battalion in a fortified village, killing 126. On April 13, however, VC overran Kien Long (near U Minh Forest), killing 300 ARVN and 200 civilians.
Command changes and continued actions
On April 25, GEN Westmoreland was named to replace GEN Harkins; an ARVN ambush near Plei Ta Nag killed 84 VC.
Ambassador Lodge resigned on June 23, with General Taylor named to replace him. In the next two days, the ARVN would succeed with Operation THANG LANG-HAI YEN 79 on the Dinh Tuong-Kien Phuong Sector border, killing 99 VC, followed the next day by an attack on a training camp in Quang Ngai, killing 50. These successes, however, must be balanced by the Buddhist crisis and the increased instability of Diem.
After Diem's fall in November, INR saw the priority during this period as more a matter of establishing a viable, sustainable political structure for South Vietnam, rather than radically improving the short-term security situation. It saw the Minh-Tho government as enjoying an initial period of popular support as it removed some of the most disliked aspects of the Diem government. During this time, the increase in VC attacks was largely coincidental; they were resulting from the VC having reached a level of offensive capability rather than capitalizing on the overthrow of Diem.
During this period, INR observed, in a December 23 paper, the U.S. needed to reexamine its strategy focused on the Strategic Hamlet Program, since it was getting much more accurate — if pessimistic — from the new government than it had from Diem. Secretary McNamara, however, testified to the House Armed Service Committee, on December 27, that only a maximum effort of American power could salvage the situation. Two days later, the Minh-Tho government was overthrown. 
North Vietnamese buildup
COL Don Si Nguyen brought in battalions of engineers to improve the Trail, principally in Laos, with up-to-date Soviet and Chinese construction equipment, with a goal, over several years, of building a supply route that could pass 10 to 20,000 soldiers per monthAt this time, the U.S. had little intelligence collection capability to detect the start of this project. Specifically, MACV-SOG, under Russell, was prohibited from any operations in Laos, although SOG was eventually authorized to make cross-border operations.
U.S. and GVN covert action planning and preparation
Before the operations scheduled by the Krulak committee could be attempted, there had to be an organization to carry them out. An obscure group called MACV-SOG appeared on the organization charts. Its overt name was "MACV Studies and Operations Group". In reality, it was the Special Operations Group, with CIA agent programs for the North gradually moving under MACV control — although SOG almost always had a CIA officer in its third-ranking position, the second-in-command being an Air Force officer. The U.S. had a shortage of covert operators, with Asian experience. in general. Ironically, Assistant Secretary of State Roger Hilsman, who had been a guerrilla in Asia during the Second World War, was forced out of office on February 24.
MG Jack Singlaub, to become the third commander of SOG, argued that special operators needed to form their own identity; while today's United States Special Operations Command has components from all the services, there is a regional Special Operations Component, alongside Army, Navy, Air Force, and Marine Components, in every geographic Unified Combatant Command. Today, officers from the special operations community have risen to four-star rank, including Chairman of the Joint Chiefs of Staff, but special operators were regarded as outcasts, unlikely to rise high in rank, during the Vietnam War.
To understand factors that contributed to the heightened readiness in the Gulf, it must be understood thatMACV-SOG OPPLAN 34A naval operations had been striking the coast in the days immediately before the incident, and at least some North Vietnamese naval patrols were deployed against these.
Possible consequences of such actions, although not explicitly addressing the OPPLAN34A operations, were assessed by the United States intelligence community in late May, on the assumption
The actions to be taken, primarily air and naval, with the GVN (US-assisted) operations against the DRV and Communist-held Laos, and might subsequently include overt US military actions. They would be on a graduated scale of intensity, ranging from reconnaissance, threats, cross-border operations, and limited strikes on logistical targets supporting DRV operations against South Vietnam and Laos, to strikes (if necessary) on a growing number of DRV military and economic targets. In the absence of all-out strikes by the DRV or Communist China, the measures foreseen would not include attacks on population centers or the use of nuclear weapons.
Further assumptions is that the U.S. would inform the DRV, China, and the Soviet Union that these attacks were of limited purpose, but show serious intent by additional measures including sending a new 5,000 troops and air elements to Thailand; deploying strong air, naval, and ground strike forces to the Western Pacific and South China Sea; and providing substantial reinforcement to the South. The U.S. would avoid further Geneva talks until it was established that they would not improve the Communist position.
It was estimated that while there would be a strong diplomatic and propaganda response, the DRV and its allies would "refrain from dramatic new attacks, and refrain from raising the level of insurrection for the moment."
For continuing chronology, see Vietnam War, Second Indochina War, external allied combat forces in South Vietnam.
- , Chapter 6, "The Advisory Build-Up, 1961-1967," Section 1, pp. 408-457, The Pentagon Papers, Gravel Edition, Volume 2 Cite error: Invalid
<ref>tag; name "PntV1Ch05Sec0314-346" defined multiple times with different content
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<ref>tag; name "INR-VN4" defined multiple times with different content Cite error: Invalid
<ref>tag; name "INR-VN4" defined multiple times with different content
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