Air operations against North Vietnam
During the Vietnam War, the United States conducted extensive air operations against North Vietnam, but few, until 1972, had decisive effect. Earlier in the war, the objectives, and to a large extent the tactics, were dictated by political leaders without understanding of air warfare, and, to a significant extent, a lack of understanding of the Vietnamese Communist grand strategy and how the leadership interpreted U.S. actions.
In retrospect, however, air operations, even with the best military technique of the time, could not have won the war, and might or might not even have significantly changed North Vietnamese conduct. While the Operation LINEBACKER I and Operation LINEBACKER II operations of 1972 had decided effect, the war had changed, by then, from guerilla and civil war in 1965 to conventional warfare. Colonel Dennis Drew argues that air power, applied in 1965, could not have had the same effect. 
Both signaling strategy and compellence played a role in the Johnson Administration's goals, although the compellence was of an atypical nature in international relations theory (i.e., #3 below) Assumptions changed, however, when the Nixon Administration took over and included #2. 
- "Coercive diplomacy" separate from the use of force, discussed by Alexander George and Janice Gross Stein: that which happens before "the first bomb is dropped". The actual use of force, as in deterrence, signifies failure, but the truly difficult part is exercising a signaling strategy understandable to all sides.
- coercion exercised almost entirely through the use of force (normally air power), in the works of Robert Pape, Daniel Byman, and Matthew Waxman; an example is the Second World War strategic bombing of Japan. A challenge here is that it is "hard to distinguish clearly between coercion and brute force given the scale and intensity of the conflicts studied."
- coercion exercised by both diplomacy and force, discussed by Schelling, Daniel Ellsberg, Wallace Thies, and Lawrence Freedman; an example is that of the "Lyndon Johnson administration to coerce the North Vietnamese government to cease its support of the Viet Cong insurgents in South Vietnam in the 1960s. In the view of a scholar who has traced this attempt, there is no sharp break between, first, coercive diplomatic efforts backed by very limited and covert use of force in 1963-64; second, limited demonstrative uses of force in reprisals after the Gulf of Tonkin incident; and third, the escalating air campaign of Operation ROLLING THUNDER."
The Johnson Administration saw the war as a proxy for great power confrontation in the Cold War, although, with the benefit of hindsight, it was far more a Vietnamese struggle for power. The Vietnamese Communists, indeed, played the Soviets and the Chinese against one another.
There was also an extreme concern, in the political leadership, that China might intervene as it did in the Korean War. This underestimates the traditional enmity of the Vietnamese against the Chinese, and also the logistical problems of Chinese ground troops at the end of a line of communications that was several hundred miles even to the South Vietnamese border. Assuming restrictions on U.S. air power had been lifted, it is unlikely that Chinese military aviation could have made much difference in the skies of North Vietnam. McGeorge Bundy said, "the fact that the President had not had formal diplomatic experience to any great extent was no true measure of the degree of his exposure to major questions in foreign affairs...there was certainly a gap in his experience in the sense that he was not widely and easily acquainted with the people concerned with the conduct and management of international affairs both in the United States and outside the United States.
Johnson saw the war in terms of its effects on domestic politics and made decisions based on domestic considerations. He did not want to be known as the Democrat who "lost Vietnam." As a believer in the "domino theory," he worried that other countries in Southeast Asia would fall to Communism if the line was not held.
The only alternative to containment, he believed, was rollback, as advocated by Barry Goldwater. "Why Not Victory?" Goldwater asked; because it means nuclear war, Johnson retorted, as he used the rollback issue to overwhelm Goldwater in the 1964 election. To be consistent with Johnson's policies, the Air Force revised its manual of air doctrine, to state that "total victory in some situations would be an unreasonable goal."
Nixon, on the other hand, did not want to suggest negotiation to the North Vietnamese, and indeed caused leaks that would suggest he was "crazy".
Aftermath of the Gulf of Tonkin incident
While aircraft attacked North Vietnamese fast attack craft in international waters, Operation PIERCE ARROW was the formal name for the retaliatory attack against naval bases, and an oil refinery at Vinh.
Intelligence, reconnaissance and surveillance
There was substantial use of unmanned aerial vehicles, principally for imagery intelligence but possibly also for signals intelligence. A limited number of SR-71 Blackbird sorties were flown for strategic imagery, and fighter-reconnaissance aircraft flew battle damage assessment missions.
The time of signaling
- Operation FLAMING DART : The first U.S. air attacks on North Vietnam, after the Gulf of Tonkin incident, by the U.S. during the Vietnam War, but before the full Operation ROLLING THUNDER campaign
- Operation ROLLING THUNDER : Initial sustained U.S. air campaign against the Democratic Republic of Vietnam (North Vietnam), based on a controversial model of retaliation and gradually increasing pressure rather than a short and intense campaign intended to destroy, not dissuade and punish
Commitment to major strikes
The LINEBACKER operations of 1972, following a bombing halt, moved from the third to the second compelence strategy. LINEBACKER II, in particular, literally destroyed -- after tactical adjustments -- North Vietnamese operational capability. LINEBACKER I had significantly disrupted the ability of North Vietnam to send troops and supplies to the south.
- Operation LINEBACKER I : A U.S. bombing campaign targeted against the specific North Vietnamese infrastructure of the Ho Chi Minh trail, with the operational-level goal of interrupting the supply line to People's Army of Viet Nam conventional troops in the South.
- Operation LINEBACKER II : The most intense air campaign of the Vietnam War, directed against North Vietnam to force it back to the Paris Peace Talks; a peace agreement was signed one month after the start of the 11 days of attacks
- Dennis M. Drew (1986), "Rolling Thunder 1965: Anatomy of a Failure", Air University Review
- Patrick C. Bratton (Summer, 2005), "When is coercion successful? And why can't we agree on it?", Naval War College Review
- Mullholan, Paige E. (January 1, 1969), Oral History Interview with McGeorge Bundy, Interview 1, pp. I-1 to I-2
- The History Channel (September 22, 1964), Goldwater attacks Johnson's Vietnam policy
- Pauly, John W. (May-June 1976), "The Thread of Doctrine", Air University Review