Operation Linebacker II, sometimes referred to as the Christmas bombing and, in Vietnam, the Twelve days and nights, or Điện Biên Phủ of the Sky, was a strategic bombing campaign conducted by the United States against military and industrial areas of North Vietnam from 18 December to 29 December 1972, during the Vietnam War. More than 20,000 tons of ordnance was dropped, primarily targeting Hanoi and Haiphong, and at least 1,624 civilians were killed.
Because of Nixon's diplomatic groundwork, neither Moscow nor Beijing intervened in the campaign. They offered verbal protests but prioritized their new relationships with Washington over their alliance with Hanoi. This isolated North Vietnam and forced them back to the negotiating table within 11 days. Many historians argue that the shifting dynamics of the strategic triangular diplomacy, which led to the Christmas bombing, played a critical role in changing the North Vietnamese's negotiating strategy and ultimately led to the signing of the Paris Peace Accords in January 1973.
By 1972, U.S. combat involvement in Vietnam had been dramatically reduced, and negotiations to end the war were underway in Paris. After secret meetings in October between lead negotiators Henry Kissinger and Le Duc Tho, an informal agreement was reached. The terms included a total U.S. withdrawal, North Vietnam's recognition of South Vietnam, new borders based on the present front lines, and new elections in the South, which would include the then-banned Communist Party of Vietnam. South Vietnamese president Nguyen Van Thieu, however, totally rejected these terms when he was informed about them and, following Richard Nixon's reelection in November, the U.S. submitted new terms, which included the Vietnamese Demilitarized Zone (DMZ) as the recognized national border, leading to a breakdown in negotiations on 16 December. Nixon issued an ultimatum for the North to return to negotiations within 72 hours, after which he ordered the bombing campaign on 18 December. Conducted by more than 200 B-52 bombers from Strategic Air Command supported by tactical planes of the Seventh Air Force and Task Force 77, the raids ran from 18 to 24 December and 26 to 29. The U.S. acknowledged the loss of 16 B-52 bombers, while North Vietnam claimed 34 bombers shot down.
The effect of the bombing on the peace negotiations is debated. On 22 December, Nixon asked the North to return to the talks with the terms offered in October and warned Thieu that he would sign the agreement even if Thieu did not. The North agreed, and Nixon ordered a halt to the bombing on 30 December. The North Vietnamese delegation stated that the campaign played no role in the decision to return to negotiations, while an aide to Kissinger remarked that "[w]e bombed the North Vietnamese into accepting our concessions". On 27 January 1973, the Paris Peace Accords were signed along the same terms as the initial October agreement.
Operation Linebacker II, sometimes referred to as the Christmas bombing and, in Vietnam, the Twelve days and nights, or Điện Biên Phủ of the Sky, was a strategic bombing campaign conducted by the United States against military and industrial areas of North Vietnam from 18 December to 29 December 1972, during the Vietnam War. More than 20,000 tons of ordnance was dropped, primarily targeting Hanoi and Haiphong, and at least 1,624 civilians were killed.
Because of Nixon's diplomatic groundwork, neither Moscow nor Beijing intervened in the campaign. They offered verbal protests but prioritized their new relationships with Washington over their alliance with Hanoi. This isolated North Vietnam and forced them back to the negotiating table within 11 days. Many historians argue that the shifting dynamics of the strategic triangular diplomacy, which led to the Christmas bombing, played a critical role in changing the North Vietnamese's negotiating strategy and ultimately led to the signing of the Paris Peace Accords in January 1973.
By 1972, U.S. combat involvement in Vietnam had been dramatically reduced, and negotiations to end the war were underway in Paris. After secret meetings in October between lead negotiators Henry Kissinger and Le Duc Tho, an informal agreement was reached. The terms included a total U.S. withdrawal, North Vietnam's recognition of South Vietnam, new borders based on the present front lines, and new elections in the South, which would include the then-banned Communist Party of Vietnam. South Vietnamese president Nguyen Van Thieu, however, totally rejected these terms when he was informed about them and, following Richard Nixon's reelection in November, the U.S. submitted new terms, which included the Vietnamese Demilitarized Zone (DMZ) as the recognized national border, leading to a breakdown in negotiations on 16 December. Nixon issued an ultimatum for the North to return to negotiations within 72 hours, after which he ordered the bombing campaign on 18 December. Conducted by more than 200 B-52 bombers from Strategic Air Command supported by tactical planes of the Seventh Air Force and Task Force 77, the raids ran from 18 to 24 December and 26 to 29. The U.S. acknowledged the loss of 16 B-52 bombers, while North Vietnam claimed 34 bombers shot down.
The effect of the bombing on the peace negotiations is debated. On 22 December, Nixon asked the North to return to the talks with the terms offered in October and warned Thieu that he would sign the agreement even if Thieu did not. The North agreed, and Nixon ordered a halt to the bombing on 30 December. The North Vietnamese delegation stated that the campaign played no role in the decision to return to negotiations, while an aide to Kissinger remarked that "[w]e bombed the North Vietnamese into accepting our concessions". On 27 January 1973, the Paris Peace Accords were signed along the same terms as the initial October agreement.
Background
"Peace is at hand"
On 8 October 1972, U.S. National Security AdvisorHenry Kissinger and North Vietnamese Politburo member Le Duc Tho met in Paris to discuss new proposals by both nations, hoping to reach mutually agreeable terms for a peace settlement for the nearly decade-old Vietnam War. Tho presented a new North Vietnamese plan which included proposals for a cease-fire, the withdrawal of American forces, and an exchange of prisoners of war. All three Vietnamese combatant governments—North Vietnam, the Republic of Vietnam (South Vietnam), and the Provisional Revolutionary Government of South Vietnam (PRG)—would remain intact, as would their separate armies. Hanoi no longer demanded that South Vietnamese president Nguyen Van Thieu be removed from office, the U.S. did not have to cease its aid to the southern government, and both Washington and Hanoi could continue to resupply their allies or forces on a parity basis. No new North Vietnamese forces were to be infiltrated from the north, and the U.S. agreed to extend post-war reconstruction assistance to North Vietnam.
The new terms on the table also included the establishment of a National Council of National Reconciliation and Concord, a loosely defined administrative structure which was to work toward general and local elections within South Vietnam. Political power would be shared by three groups: the Saigon government, the PRG, and a "third force" group to be mutually agreed upon by the other two parties. Since it was to work by consensus, nothing could be accomplished by the new council without the agreement of President Thieu.
When the two sides convened again on 17 October, there were two main areas of disagreement: the periodic replacement of South Vietnam's American weaponry and the release of political prisoners held by the Saigon government. The North Vietnamese had made significant modifications to their past negotiating position and were hurrying to get the agreement signed before November, believing that President Richard Nixon would be more willing to make concessions before, rather than after, the upcoming presidential election. Although there were still some issues to be finalized, Kissinger was generally satisfied with the new terms and so notified Nixon, who gave his approval to the settlement.
Kissinger then flew on to Saigon on the 18th to discuss the terms with Thieu. The South Vietnamese president was not happy with either the new agreement or with Kissinger, who he felt had betrayed him. Although Kissinger knew Thieu's negotiating position, he had not informed him of the changes made in Paris nor had his approval been sought. Kissinger "had negotiated on behalf of the South Vietnamese government provisions that he, Thieu, had already rejected". Thieu completely castigated the agreement and proposed 129 textual changes to the document. He went further, demanding that the Demilitarized Zone separating the two Vietnams be recognized as a true international border and not as a "provisional military demarcation line" (as had been stipulated in the Geneva Accords) and that South Vietnam be recognized as a sovereign state. The supreme irony, in the words of Stanley Karnow, had now arrived: "having fought a war to defend South Vietnam's independence, the United States was now denying its legitimacy."
Thieu then went one step further on 26 October, and publicly released an altered version of the text that made the South Vietnamese provisions look even worse than they actually were. The North Vietnamese leadership, believing that they had been deceived by Kissinger, responded by broadcasting portions of the agreement that gave the impression that the agreement conformed to Washington and Saigon's objectives. Kissinger, hoping to both reassure the Communists of America's sincerity, and convince Thieu of the administration's dedication to a compromise, held a televised press conference at the White House during which he announced "[w]e believe that peace is at hand."
On 20 November, the South Vietnamese revisions, and 44 additional changes demanded by Nixon, were presented to the North Vietnamese delegation by Kissinger. These new demands included: that the DMZ be accepted as a true international boundary; that a token withdrawal of North Vietnamese troops take place; that the North Vietnamese guarantee an Indochina-wide cease fire; and that a strong international peace-keeping force (the ICCS) be created for supervising and enforcing the cease-fire.<
Once the North Vietnamese read the new demands, they began to retract their own concessions and wanted to bargain anew, leading Kissinger to proclaim that they were "stalling". The talks, scheduled to last ten days, ended on 13 December, with both parties agreeing to resume negotiations. Teams of experts from each side met to discuss technicalities and protocols on 14 December, during which time the North Vietnamese representatives submitted a Vietnamese-language text of the protocol on prisoners containing several important changes that Hanoi had failed to gain in the main negotiating sessions. At a subsequent meeting of experts on 16 December, the North Vietnamese side "stone-walled from beginning to end". The talks broke down that day, and the Hanoi negotiators refused to set a date for the resumption of negotiations.
Prelude
Decisions
Nixon was now working against a January deadline. Kissinger's "peace is at hand" statement had raised expectations of a settlement among Americans. Even weightier on the President's mind was the fact that the new 93rd Congress would go into session on 3 January, and the President feared that the heavily Democratic legislative branch would preempt his pledge of "peace with honor" by legislating an end to the war.
Also prompting the President toward some form of rapid offensive action was the cost of the force mobilization that had accompanied Operation Linebacker. The additional aircraft and personnel assigned to Southeast Asia for the operation was straining the Pentagon's budget. The cost of maintaining this "augmentation force" totaled over $4 billion by mid-autumn and Secretary of DefenseMelvin Laird insisted that the President request a supplementary defense appropriation from Congress to pay for it. Nixon and Kissinger were convinced that the legislative branch "would seize the opportunity to simply write the United States out of the war".
After returning from Paris on 14 December, and after consultations with Nixon, Kissinger fired off an ultimatum to Hanoi, threatening "grave consequences" if North Vietnam did not return to the negotiating table within 72 hours. On that day, Nixon ordered the reseeding of North Vietnamese ports with air-dropped naval mines and that the Joint Chiefs of Staff direct the Air Force to begin planning for a bombing campaign (a three-day "maximum effort" operation) which was to begin within 72 hours. Two days after the 16 December deadline had passed, the U.S. bombed Hanoi. Senior Air Force officers James R. McCarthy and George B. Allison stated years later that the operation had been mainly politically driven, as a negotiation tool to "bring the point home".
Many historians of the Vietnam War follow the lead of President Nixon, who claimed that Hanoi's representatives had walked out of the talks, refusing to continue the negotiations. Both sides had proclaimed their willingness to continue the talks; however, Hanoi's negotiators refused to set a date, preferring to wait for the incoming Congress. The goal of President Nixon was not to convince Hanoi, but to convince Saigon. President Thieu had to be assured that "whatever the formal wording of the cease-fire agreement, he could count on Nixon to come to the defense of South Vietnam if the North broke the cease-fire."
Planning
In the wake of Operation Linebacker, the U.S. had a force of 207 B-52 bombers available for use in Southeast Asia. A total of 54 bombers (all B-52Ds) were based at U-Tapao RTAFB in Thailand, while 153 were based at Andersen Air Force Base in Guam (55 B-52Ds and 98 B-52Gs). This deployment comprised nearly half of the Air Force's manned bomber fleet, and Strategic Air Command (SAC) commanders were initially reluctant to risk the expensive aircraft and their highly trained crews in such an operation; the production line for B-52s had long since been shut down, and losses could not be replaced.The use of large numbers of B-52s was unprecedented in the war and the proposed mass attacks on targets within 10 nautical miles (20 km) of Hanoi "represented a dynamic change in the employment of air resources".
The new operation, given the title Linebacker II, was marked by top-down planning by the SAC headquarters at Offutt AFB. Due to the restrictive time frame imposed by President Nixon (only three days) and the experience of Linebacker (in which North Vietnamese fighter aircraft had posed the highest threat to the bombers), SAC's plan called for all of the bombers to approach Hanoi at night in three waves, each using identical approach paths and flying at the same altitude.
Once the aircraft had dropped their bombs, they were to execute what SAC termed "post-target turns" (PTT) to the west. These turns had two unfortunate consequences for the bombers: the B-52s would be turning into a strong headwind, slowing their ground speed by 100 kn (120 mph; 190 km/h) and prolonging their stay in the target area and the PTT would point the emitter antennas of their Electronic Warfare (EW) systems away from the radars they were attempting to jam, degrading the effectiveness of the cells, as well as showing the largest radar cross-section to the missile guidance radars. The aircraft employed had significantly different EW capabilities; the B-52G carried fewer jammers and put out appreciably less power than the B-52Ds but had more efficient engines and larger fuel tanks, hence they were assigned to longer range mission routes.
Vietnamese air defense
At the start of Operation Linebacker II, North Vietnam's air defense consisted of 36 missile battalions equipped with the SovietS-75M Dvina (SA-2 Guideline). Although this missile system was first introduced in 1957 and was considered somewhat outdated by 1972 standards, about half of these units were actively involved in the operation. The Vietnamese People's Air Force (VPAF) had a small fleet of only 71 operational aircraft, and of those, only 47 (including 31 MiG-21s and 16 MiG-17s) were suitable for air combat. While they also had MiG-19s made in China, these were not used in actual combat. Out of nearly 200 pilots, only 13 MiG-21 pilots and five MiG-17 pilots were trained to fly at night or in difficult weather conditions. Approximately 40% (75 out of 194) of the pilots were relatively young and less experienced.
Bombing
Initial phase
The first three missions of the operation were flown as planned by SAC on three consecutive nights beginning on 18 December 1972. On the first night 129 bombers took off, 87 of them from Guam. 39 support aircraft of the Seventh Air Force, the Navy's Task Force 77 and the Marine Corps supported the bombers by providing F-4 Phantom fighter escorts, Republic F-105 ThunderchiefWild Weasel SAM-suppression missions, Air Force Douglas EB-66 Destroyer and Navy Grumman EA-6 Prowler radar-jamming aircraft, chaff drops, KC-135 refueling aircraft and search and rescue aircraft; the skies were dominated by American airpower to ensure the safety of the aircraft involved in the operation. One B-52 bomber pilot flying out of Guam recalled: "We took off one airplane a minute out of Guam for hours. Just on time takeoff after on time takeoff."