Operation Menu in Cambodia, March 1969. Source: Vietnam: The Art of War website
On 18th March 1969, Nixon authorised Operation Menu, an intense US air force bombing campaign in eastern Cambodia, targeting the Viet Cong and North Vietnamese military sanctuaries which had long provided the bases from which Communist forces could launch attacks across South Vietnam. Although Sihanouk had, in the past, tacitly agreed with such action, the ferocity and extent of the bombing was far greater than the Cambodian leader anticipated. It destabilised his precarious balancing act between the competing forces of the Second Indochina War, and emboldened his right wing opponents against his neutralist tactics. It also led directly to a surge of support for the Khmer Rouge amongst the peasantry in the areas affected by the bombing: over the next three years, over 500,000 tons of bombs would be dropped on Cambodia.
Crucially, Nixon and Kissinger kept the bombing secret from Congress and the American public, taking the view that given Nixon’s promise to de-escalate the Vietnam War, such an expansion of operations would be politically unacceptable. In the same month, Secretary of Defence Melvin Laird came up with the phrase “Vietnamisation” to describe the process by which the ARVN were expected to make up the slow reduction in American troop numbers with South Vietnamese soldiers.
