Lyndon B. Johnson shared the Cold War assumptions underlying Kennedy’s foreign policy. Retaining Kennedy’s key advisers—Secretary of State Dean Rusk, Secretary of Defense Robert McNamara, and National Security Adviser McGeorge Bundy—Johnson continued the massive buildup of nuclear weapons as well as conventional and counterinsurgency forces. In 1965, he made the fateful decisions to order U.S. troops into combat in Vietnam and to initiate sustained bombing of the North. That same year, Johnson sent U.S. Marines to crush a leftist rebellion in the Dominican Republic.