On February 26, 1965, President Lyndon B. Johnson approved the dispatch of a Marine force to Danang, South Vietnam. At first, this Marine force’s only mission was to provide security to the U.S. air base and military compound against enemy attack. By April 1965, U.S. policymakers
developed the “enclave” strategy. With the deteriorating ARVN military situation, the “enclave” strategy was supplanted by the “search and destroy” strategy. This change in strategy and the military situation led to General William Westmoreland’s call for offensive operations by the in-country U.S. forces, particularly the U.S. Marine units in the I Corps Area, and the first step toward the “Americanization” of the Vietnam War.