Robert S. McNamara served as U.S. Secretary of Defense (SOD) for Presidents John Kennedy and Lyndon Johnson. McNamara participated in the Cuban Missile Crisis negotiations in 1961 and became a key formulator of Vietnam policy. This thesis challenges scholarship that characterizes McNamara as a fierce hawk who relentlessly executed military escalation in Vietnam. By drawing parallels between McNamara’s role in the Cuban Missile Crisis and the Vietnam War, and by exploring how McNamara’s concept of loyalty to the presidency influenced his decisions, this thesis argues that the SOD was willing to escalate the situation militarily as a form of political communication with the adversary. To McNamara, military pressure was a means to create avenues for diplomacy. McNamara became increasingly uncomfortable – and ultimately resigned in 1968 - when the Johnson administration pursued military escalation without an organized campaign towards negotiations. He was therefore not as hawkish as other scholars have claimed. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection