Privately, Johnson agonized over the consequences of the U.S. escalation in Vietnam and raged at the incompetence of the succession of military juntas that tried to govern that country and carry on a war against Viet Cong guerrillas and North Vietnamese regulars. Publicly, he was determined not to lose the war. As a result, in 1968 there were 500,000 American troops in South Vietnam and no end in sight to the conflict. After an extensive re-examination, President Johnson decided to disengage from a struggle lacking U.S. domestic support. He desperately tried to initiate formal peace negotiations in Paris before the 1968 presidential election, but the peace talks commenced only as he left office.
Johnson was also concerned about Latin American policy, which was another of his special interests. He chose Eisenhower official Thomas C. Mann to be Assistant Secretary of State for Inter-American Affairs. Mann let it be known that he would judge Western Hemisphere neighbors by their commitment to anti-communism rather than their commitment to democracy. The Alliance for Progress, begun with such fanfare under Kennedy, was allowed to wither as a result of neglect and its own internal problems. Johnson’s policy toward Latin America became increasingly interventionist, culminating with the deployment of U.S. soldiers to Santo Domingo to prevent another communist takeover in the Caribbean.