Role of the United States in the Vietnam War the presidency unopposed. With the installation of the Thieu and Ky government (the Second Republic), the U.S. had a pliable, stable, and semi-legitimate government in Saigon with which to deal. With the advent of "Rolling Thunder", American airbases and facilities needed to be constructed and manned for the aerial effort. On March 8, 1965, 3,500 United States Marines came ashore at Da Nang as the first wave of U.S. combat troops into South Vietnam, adding to the 25,000 U.S. military advisers already in place. The US Government deployment of ground forces to Da Nang had not been consulted with the
1965 in the Vietnam War revealed that Thao was a communist agent. General William Westmoreland, commander of MACV, requested that two battalions of United States Marines be assigned to protect the airbase at Da Nang from the increasing threat of attacks by the Viet Cong. General Khánh departed South Vietnam. He was persuaded to leave by his fellow generals and by Colonel Wilson of MACV. Air Marshall Nguyễn Cao Kỳ became the de facto leader of South Vietnam. The first South Korean troops arrived in South Vietnam. The number of South Korean troops in South Vietnam would total 49,755 by 1969. The U.S. paid most