In the fall of 2000, twenty-five years after the end of the war in Indochina, Bill Clinton became the first US president since Richard Nixon to visit Vietnam. While media coverage of the trip was dominated by talk of some two thousand US soldiers still classified as missing in action, a small act of great historical importance went almost unnoticed. As a humanitarian gesture, Clinton released extensive Air Force data on all American bombings of Indochina between 1964 and 1975. Recorded using a groundbreaking ibm-designed system, the database provided extensive information on sorties conducted over Vietnam, Laos, and Cambodia. Clinton’s gift was intended to assist in the search for unexploded ordnance left behind during the carpet bombing of the region. Littering the countryside, often submerged under farmland, this ordnance remains a significant humanitarian concern. It has maimed and killed farmers, and rendered valuable land all but unusable. Development and demining organizations have put the Air Force data to good use over the past six years, but have done so without noting its full implications, which turn out to be staggering.

The still-incomplete database (it has several “dark” periods) reveals that from October 4, 1965, to August 15, 1973, the United States dropped far more ordnance on Cambodia than was previously believed: 2,756,941 tons’ worth, dropped in 230,516 sorties on 113,716 sites. Just over 10 percent of this bombing was indiscriminate, with 3,580 of the sites listed as having “unknown” targets and another 8,238 sites having no target listed at all. The database also shows that the bombing began four years earlier than is widely believed—not under Nixon, but under Lyndon Johnson. The impact of this bombing, the subject of much debate for the past three decades, is now clearer than ever. Civilian casualties in Cambodia drove an enraged populace into the arms of an insurgency that had enjoyed relatively little support until the bombing began, setting in motion the expansion of the Vietnam War deeper into Cambodia, a coup d’état in 1970, the rapid rise of the Khmer Rouge, and ultimately the Cambodian genocide. The data demonstrates that the way a country chooses to exit a conflict can have disastrous consequences. It therefore speaks to contempor­ary warfare as well, including US operations in Iraq. Despite many differences, a critical similarity links the war in Iraq with the Cambodian conflict: an increasing reliance on air power to battle a heterogeneous, volatile insurgency.

We heard a terrifying noise which shook the ground; it was as if the earth trembled, rose up and opened beneath our feet. Enormous explosions lit up the sky like huge bolts of lightning; it was the American B-52s.
— Cambodian bombing survivor

On December 9, 1970, US President Richard Nixon telephoned his national-security adviser, Henry Kissinger, to discuss the ongoing bombing of Cambodia. This sideshow to the war in Vietnam, begun in 1965 under the Johnson administration, had already seen 475,515 tons of ordnance dropped on Cambodia, which had been a neutral kingdom until nine months before the phone call, when pro-US General Lon Nol seized power. The first intense series of bombings, the Menu campaign on targets in Cambodia’s border areas — labelled Breakfast, Lunch, Supper, Dinner, Dessert, and Snack by American commanders — had concluded in May, shortly after the coup.

Nixon was facing growing congressional opposition to his Indochina policy. A joint US–South Vietnam ground invasion of Cambodia in May and June of 1970 had failed to root out Vietnamese Communists, and Nixon now wanted to covertly escalate the air attacks, which were aimed at destroying the mobile headquarters of the Viet Cong and the North Vietnamese Army (vc/nva) in the Cambodian jungle. After telling Kissinger that the US Air Force was being unimaginative, Nixon demanded more bombing, deeper into the country: “They have got to go in there and I mean really go in...I want everything that can fly to go in there and crack the hell out of them. There is no limitation on mileage and there is no limitation on budget. Is that clear?”

Kissinger knew that this order ignored Nixon’s promise to Congress that US planes would remain within thirty kilometres of the Vietnamese border, his own assurances to the public that bombing would not take place within a kilometre of any village, and military assessments stating that air strikes were like poking a beehive with a stick. He responded hesitantly: “The problem is, Mr. President, the Air Force is designed to fight an air battle against the Soviet Union. They are not designed for this war...in fact, they are not designed for any war we are likely to have to fight.”

Five minutes after his conversation with Nixon ended, Kissinger called General Alexander Haig to relay the new orders from the president: “He wants a massive bombing campaign in Cambodia. He doesn’t want to hear anything. It’s an order, it’s to be done. Anything that flies, on anything that moves. You got that?” The response from Haig, barely audible on tape, sounds like laughter.

The US bombing of Cambodia remains a divisive and iconic topic. It was a mobilizing issue for the antiwar movement and is still cited regularly as an example of American war crimes. Writers such as Noam Chomsky, Christopher Hitchens, and William Shawcross emerged as influential political voices after condemning the bombing and the foreign policy it symbolized.

In the years since the Vietnam War,something of a consensus has emerged on the extent of US involvement in Cambodia. The details are controversial, but the narrative begins on March 18, 1969, when the United States launched the Menu campaign. The joint US–South Vietnam ground offensive followed. For the next three years, the United States continued with air strikes under Nixon’s orders, hitting deep inside Cambodia’s borders, first to root out the vc/nva and later to protect the Lon Nol regime from growing numbers of Cambodian Communist forces. Congress cut funding for the war and imposed an end to the bombing on August 15, 1973, amid calls for Nixon’s impeachment for his deceit in escalating the campaign.

Thanks to the database, we now know that the US bombardment started three-and-a-half years earlier, in 1965, under the Johnson administration. What happened in 1969 was not the start of bombings in Cambodia but the escalation into carpet bombing. From 1965 to 1968, 2,565 sorties took place over Cambodia, with 214 tons of bombs dropped. These early strikes were likely tactical, designed to support the nearly two thousand secret ground incursions conducted by the cia and US Special Forces during that period. B-52s—long-range bombers capable of carrying very heavy loads — were not deployed, whether out of concern for Cambodian lives or the country’s neutrality, or because carpet bombing was believed to be of limited strategic value.