It became an offensive, crucial to General Westmoreland’s second phase. In his three phase strategy, the first consisted of slowing down the Vietcong Forces; the second was to resume the offensive and destroy the enemy; and the third to restore the area under South Vietnamese government control. The Zippo missions, were mainly assigned to the second phase around 1966 and 1967, along with operations “Clear and Secure.”
The idea was to insert ground forces into hostile territory on special missions to target enemy forces and withdraw immediately afterwards, a strategy that was thought to be ideally suited for counter-guerrilla / jungle warfare. The complementary conventional strategy, which entailed attacking and conquering an enemy position, then fortifying and holding it indefinitely, was known as Clear and Hold or Clear and Secure. In theory, all missions were to secure and enhance confidence amongst the South Vietnamese, however search and destroy became more widely used amongst increasingly aggressive U.S. forces.
S&D missions entailed sending out a Platoon or Company (or larger detachment) of US troops from a fortified position to locate and destroy Vietcong (VC) or NVA units in the countryside. These missions most commonly involved hiking out into the "boonies" and setting an ambush in the brush, near a suspected VC trail. The ambush typically involved use of fixed Claymore Anti-personnel mines, crossing lines of Small arms fire, Mortar support, and possibly additional Artillery support called in via radio from a nearby Firebase.
In February 1967, the largest Zippo mission was operated in the Iron Triangle, located between Saigon and Routes 13 and 25. The area consisted of a mass centre of Viet Cong logistics and headquarters, where they had been operating plans for Saigon. The offensive began with Operation Junction City where the American units assigned had destroyed hundreds of tons of rice, killed 720 guerillas, and captured 213 prisoners. By destroying the headquarters, they disrupted any enemy plans for Saigon. Both Search and Destroy and Clearing missions stretched into the third phase beginning in 1968. The number of missions mounted, especially after the U.S. was hit by the General Vo Nguyen Giap’s Tet offensive attack of 1968. As the war grew more aggressive, so did the missions, to the point where there was lack of precision between Search and Destroy, and Clear and Secure operations.
Search and destroy missions had many flaws. First, there was lack of precision between “clearing” and search and destroy missions. Thus “clearing” missions, which were less aggressive, eventually morphed into a more violent and brutal form of tactics just as search and destroy missions were. With the lack of precision between “clearing” and search and destroy missions, pacification was not pushed. In American Strategy in Vietnam: The Postwar Debate, George C. Harring refers to Guenter Lewey, a Professor of Political Science at the University of Massachusetts who argues that the Generals and war planners severely underestimated the enemy’s abilities to match and exceed U.S. forces. Large numbers of Viet Cong troops would be killed or captured, however they were quickly replaced. Although, enemy forces were pushed out of certain territories, as soon as the American forces left the areas, the North Vietnamese returned with more reinforcement. Zippo missions were counterproductive towards the U.S. objective in South Vietnam. They destroyed the countryside and rice patties, weakening the economic productivity and creating inflation in South Vietnam. They created millions of refugees who lost their homes due to the missions that called for the destroying and setting fire to their bamboo houses. Moreover, with many refugees, and a damaged economic system, the missions hurt the political and social system in South Vietnam.
They also caused many American and Vietnamese causalities. In one of the first Search and Destroy missions northwest of Dau Tieng, named Operation Attleboro, the report states 155 U.S. soldiers were killed, where North Vietnamese lost 1,106. In Operation Junction City, the report states 282 U.S. soldiers killed where the Viet Cong lost 1,728 guerrillas.