Air operations in the Vietnam War

In the period from the early 1960s until the fall of South Vietnam, the United States conducted air operations against North Vietnam. Some of these missions were information-gathering intelligence missions that might not actually cross into North Vietnamese airspace. Others were intended to fight the North Vietnamese, usually attacking specific ground targets or sometimes aspects of the increasingly integrated air defense system (IADS). There were also various covert air operations against the north, with a general goal of increasing internal stress, pressure, and diverting resources.

The combat operations several into four rough phases, perhaps separated by cease-fires during which intelligence collection and other support missions (e.g., weather reporting, search and rescue, transport would continue. Those phases were:
 * 1) Retaliation for specific Communist attacks against non-Communist land or sea targets, or the reasonable belief there was an attack
 * 2) Operation ROLLING THUNDER, a period of attacks to "signal" the seriousness of U.S. attack, rather than necessarily to achieve a specific tactical, operational, or strategic result,
 * 3) Various operations against infiltration from the North into the south, often through the [Ho Chi Minh Trail]] sanctuaries in Laos and Cambodia, with the operational goal of making the ground forces in the south less efficient,
 * 4) Operation LINEBACKER I, a campaign of attacks, in the spring to fall of 1972, intended to achieve the operational goal of stopping the Eastertide conventional invention of the South by disabling the logistical support infrastructure; it was understood this infrastructure could be repaired. As far as targeting, however, a truck preparing to go onto the the Trail or moving onto the Trail, as well as facilities on the Trail, were fair targets. A ship bringing, into North Vietnam, the supplies to go on that truck was less of a target; the goal was more preventing it from unloading rather than destroying it.
 * 5) Operation LINEBACKER II, a strategic and operational campaign of short duration but greatly increased intensity, with the grand strategic goal of forcing the North Vietnamese back to the abandoned Paris Peace Talks, and the operational goals of massive destruction of the logistical infrastructure needed to get supplies in and out of the north, as well as disabling the air defense system and disruption command and control.

These efforts were generally separate from combat and noncombat air support to combat in the South, with overlap involving attacks on the Trail between the North and South, or supply distribution in the South.

Retaliatory raids
From roughly August 1964 to began with the response to the Gulf of Tonkin incident, followed by a pair of responses in February 1965, under the Operation FLAMING DART, to Communist attacks against allied facilities and troops in the South.

Signaling
Essentially starting in March 1965 and extending until the Nixon Administration took control in January 1969, these were intended to signal implacable U.S. determination to the Northern Government. This determination was intended to be perceived as meaning intensity would gradually increase until the damage became unacceptable to the North, but refrained from actually causing extensive damage.