Cambodian Incursion represented a major turning point for American sentiment towards its participation in the Vietnam War (Nolan, 1990, p. xiii). Authorized by President Nixon, it was hoped that this offensive would secure the future of South Vietnam as a non-communist nation, but the strong negative reaction by the American public, towards what seemed to be an escalation, caught the administration off guard. However, many military strategists viewed the Cambodian Incursion to be a wise decision. This essay will examine the circumstances that led to this decision and whether the offensive was successful both politically and militarily.
Events that Set the Stage for the Cambodian Incursion
The Vietnam War (1954-1975), on a global scale, represented a political struggle between the major communist and western powers for ideological control of satellite nations (Shaw, 2005, p 3). Immediately adjacent to China were four countries, Laos, Cambodia, North Vietnam, and S. Vietnam, which Hanoi, the capitol of N. Vietnam, treated as a single political entity. However, S. Vietnam wished to remain a separate nation and received considerable support from first France and then the United States in pursuit of this goal. A non-communist S. Vietnam was also seen by Washington as strategically important given its proximity to China.
S. Vietnam therefore took a defensive position, while North Vietnam took an offensive strategy towards unification under communist rule (Shaw, 2005, p. 3). By the time U.S. forces began to arrive in S. Vietnam, the Viet Cong (VC) and North Vietnamese Army (NVA) were well established within S. Vietnam and camped within 15 miles of the capitol Saigon (Coleman, 1991, p. 3). U.S. forces then began to systematically eradicate these bases from around Saigon, pushing the enemy forces closer to the demilitarized zone between North and South Vietnam, and the border region with communist Cambodia.
As a result, VC and NVA forces found sanctuary inside and along the border with Cambodia (Coleman, 1991, p. 3). This area already contained communist forces supply bases, which were supported by Hanoi via the Ho Chi Minh Trail. The Ho Chi Minh Trail exited N. Vietnam and ran through first Laos and then Cambodia. Since Washington recognized Cambodia as a neutral country, it could not simply send its forces across the border to eliminate these sanctuaries. The communist leaders of Cambodia also refused to give S. Vietnam or the United States permission to cross its borders (Tho, 1970, p. 12-16).
On March 18, 1970, the leadership of Cambodia was overthrown and the new government established a hard line against communists (Tho, 1970, p. 16). Accordingly, it gave notice to North Vietnam and the VC that they were no longer welcome and began military operations to eliminate these forces from within its borders. In response, NVA and VC troops began to fight back against the new government. Cambodia then appealed to the United Nations for help and reestablished diplomatic relations with S. Vietnam.
A year earlier President Nixon had announced the gradual pullout of American troops from S. Vietnam (Tho, 1979, p. 2-3). Between June 1969 and January 1970, 115,000 American troops left for home. Washington was therefore faced with an opportunity to increase the ability of S. Vietnam's military to successfully defend its borders, by eliminating the NVA and VC bases along the Cambodian border before all U.S. troops had left. It was suggested that missing this opportunity could delay U.S. troop withdrawal, because VC and NVA troops would not be so considerate as to allow the American troops to simply leave unharassed (Tho, 1979, p. 35).
While U.S. And S. Vietnamese commanders were preparing plans for a major offensive into Cambodia, which was to take place during the months of May and June, S. Vietnamese and Cambodian troops began their own skirmishes against NVA and VC bases on both sides of the border (Tho, 1979, p. 39-47). These operations were planned with the help of U.S. commanders and supported by U.S. units from within S. Vietnam. In the Angel's Wing border area, S. Vietnamese forces over the course of three days lost one helicopter and suffered 67 wounded and 8 killed. By contrast, 415 enemy soldiers were killed or captured, a large number of weapons seized, and 200 tons of rice confiscated. Although these skirmishes were generally successful, they also alerted the NVA and VC to the possibility of future increased hostilities along the border region (Shaw, 2005, p. 60).
The plans for the incursion into Cambodia called for III Corps (U.S.) to enter the Angel's Wing and Parrot's Beak area, and then move westward towards Phnom Penh, the capitol of Cambodia (Shaw, 2005, p. 59). The 1st Calvary Division and 11th Armored Calvary Regiment would cross north of Saigon, at an area called the Fishhook, with air support from the 11th Aviation Group and artillery support from II Field Force Vietnam. The 25th Infantry Division would enter Cambodia north of Angel's Wing and west of Fishhook.
To gain an element of surprise, U.S. commanders did not engage in the normal buildup of supplies or forces along the border region in anticipation of a major military offensive (Shaw, 2005, p. 59, 69). This meant American troops would have to begin the incursion with the equipment, munitions, and supplies that were already amassed along the border. So it came as a bit of a surprise to the VC and NVA troops encamped within Cambodia when on May 1, between 0400 and 0600 hours, 36 American B-52 bombers dropped 774 tons of bombs on the Fishhook region inside Cambodia. Between 0600 and 0700, artillery pounded known or suspected NVA and VC bases. During the next hour, fighter bombers worked on these positions. Helicopters then entered the area to attack enemy troops and reconnoiter troop landing sites. At 1000 hours, the first U.S. troops entered Cambodia and Nixon announced the incursion on American TV. Two months later, the incursion was over and all American troops were back in S. Vietnam (Shaw, 2005, p. 155).
The element of surprise and the magnitude of the offensive were successful in destroying the NVA and VC sanctuaries inside Cambodia (Shaw, 2005, p. 151-152). The confiscation of weapons and food, together with air strikes to damage the Ho Chi Minh Trail, prevented the remaining communist troops from reorganizing into an effective fighting force. The captured ammunition could have supplied all VC and NVA in S. Vietnam for 10 months, the rice could have fed 25,000 troops for a year, and the weapons outfitted 74 NVA infantry battalions (Coleman, 1991, p. 265). An estimated 11,369 enemy soldiers were killed and 2,328 captured. By contrast, 976 allied soldiers were killed, including 338 Americans. Of the 48 soldiers captured by the VC and NVA, 13 were American.
The S. Vietnamese general, Do Cao Tri, continued to make fruitful cross-border incursions against the VC and NVA troops still in Cambodia (Coleman, 1991, p. 263). However, General Tri had systematically prevented the inclusion of incompetent, politicized commanders in his ranks. General Tri's successes therefore turned out to be an aberration within S. Vietnam's military. The ineptitude pervasive in other units predicted the eventual demise of S. Vietnam's military at the hands of the NVA and VC, but the resulting lull in hostilities provided enough room for U.S. troops to comfortably and safely withdraw.
Within the United States however, the opposition to the war escalated significantly (Shaw, 2005, p. 153-154). Close to 450 colleges and universities went on strike, 6 students died during protests at Kent State and Jackson State, 3 National Security Council and 250 State Department staffers resigned in protest, and 60,000 to 100,000 protesters marched on Washington. In addition, outraged congressmen reacted by proposing two bills that would end or curtail funding for military operations in Indochina. The increasingly strident domestic hostility towards the Nixon Administration's handling…