McNamara’s appreciation of the military problems in Vietnam was intimately connected to economic developments in Washington. A continued balance of payments deficit and an unsettled domestic economic picture heightened the administration’s sense of vulnerability. The Senate Foreign Relations Committee (SFRC) exerted new pressure on the Military Assistance Program (MAP) that funded operations in Vietnam. With Dillon, McNamara worked on a Cabinet Committee on the Balance of Payments that recommended significant troop redeployments around the world. The JCS and State Department stymied their efforts. In this context, McNamara met with the famed economist John Kenneth Galbraith, who was especially critical of the growing commitment in Vietnam. McNamara chose a counterinsurgency strategy in Vietnam because it was cheaper as it relied on local forces. As Galbraith and others recommended, McNamara moved to downgrade the relative importance of South Vietnam to US security and to emphasize that the conflict was an internal insurgency. He used the pressures on the MAP to accelerate the phaseout of the US presence in South Vietnam.

When Robert McNamara accepted President Kennedy’s offer to serve as the United States’ eighth Secretary of Defense, the role was still new, a barely decade-old innovation emanating from World War II. As a young agency, the OSD was still defining its place in the national security decision-making landscape and, in so doing, trying to find the appropriate balance of power between civilian and military authorities. President Eisenhower had left the new administration with the Defense Reorganization Act of 1958, a congressionally mandated program for change at the Department of Defense. McNamara recognized its sweeping potential to pave the way for his bureaucratic revolutions as the longest-serving Secretary of Defense.

In October 1963, McNamara went to Vietnam with the chairman of the Joint Chiefs of Staff, Maxwell Taylor. On his return, the administration convened a series of NSC meetings that culminated in a press release that the United States would withdraw by 1965. The end point for the withdrawal plans and for the announcement were not victory in the traditional sense but instead something more ambiguous: “until the insurgency has been suppressed or that national security forces of the Government of South Viet-Nam are capable of suppressing it.” Over the last few months and especially in October, McNamara was concerned with what he found in Vietnam where existing programs were deficient or lagging. Withdrawal was not premised on success but instead on a predetermined training program that fit with McNamara’s priorities at the OSD. He insisted on a public announcement as a bureaucratic move aimed at neutralizing those who might interrupt the CPSVN. A separate announcement that 1,000 troops would be withdrawn by December 1963 was aimed at quieting SFRC criticism that the United States was bogged down in Vietnam.

The year 1966 was one of interlocking crises. The consequences of escalation in Vietnam ricocheted onto the domestic and global economy. The SFRC and SASC blamed McNamara for the administration’s economic and political obfuscations. Stung by congressional criticism and the label of “McNamara’s war,” McNamara set out to restore his reputation and protect his legacy at the Defense Department. His friendship with “Bobby” exacerbated his disenchantment with the war and strained his loyalty to Johnson to the breaking point. Like many Kennedy holdovers, he drew unfavorable comparisons between the two Presidents that he had served. In Vietnam, despite a burst of diplomatic activity, the prospect of a negotiated settlement in Vietnam all but ended. Instead, escalation continued with no clear objective in sight. With nothing left to lose, McNamara stepped out of his self-imposed restrictions and began to question the administration’s strategy. He returned to the ideas that he had defended in the Kennedy administration and, in 1967, bypassed the State Department and stepped in to run a peace overture himself.

Roger Hilsman and Robert Thompson prepared plans for Vietnam that counterbalanced the increasing pressure to deploy troops. Thompson had a great influence on McNamara. He informed the Secretary’s frustrations with the US mission’s inability to coordinate existing programs and with the Chiefs’ focus on conventional tools. By July, McNamara instructed the Chiefs to prepare a phaseout plan for US advisors in Vietnam, which was called the Comprehensive Plan for South Vietnam (CPSVN). It was designed to train the South Vietnamese to fight the communist insurgency themselves. Growing unrest in South Vietnam did not dampen these plans; instead, they accelerated. A phaseout brought order to existing programs and promised to secure their long-term funding.

President Lyndon B. Johnson was inclined to favor “tougher” military responses that promised victory. He understood the intricacies of the policy that he had inherited but changed it. He promoted Rusk to the detriment of other advisors who had supported a counterinsurgency program and who left, including Hilsman, Michael Forrestal and Ted Sorensen. McNamara initially resisted expanding the commitment in Vietnam. In a presidential election year, he was sent on two trips to South Vietnam, in March and May, that were designed to placate possible critics of Johnson’s policies, including the JCS, Ambassador Lodge, the Senate Armed Services Committee (SASC) and the SFRC. Johnson pressed his Secretary to give the Chiefs “something” militarily. In response, McNamara looked for “disavowable actions” and eventually moved to support a bombing program as a substitute for deploying ground troops.

McNamara moved more forcefully than any of his predecessors in implementing civilian control over the military, with a contemptuous and domineering attitude toward the Joint Chiefs of Staff (JCS). His most important managerial innovations were designed to enforce “subjective control,” namely to impose civilian objectives and ideas on the military. The Draft Presidential Memoranda (DPMs) and the Planning, Programming and Budgeting System (PPBS) were designed to align military tools to civilian-defined foreign and economic policies. He worked closely with Secretary of State Dean Rusk to align military tools to the President’s foreign policy and with Secretary of the Treasury C. Douglas Dillon to ensure the Defense Department’s programs fit within a framework of fiscal discipline.

President John F. Kennedy was elected on a program of change. Despite his electoral rhetoric, in office, he was cautious and fiscally conservative. He felt especially vulnerable on economic issues with a nagging balance of payments deficit that threatened the role of the dollar in the international monetary system. He chose Republicans for the two agencies that had the greatest bearing on the balance of payments: C. Douglas Dillon as Secretary of the Treasury and McNamara as Secretary of Defense. At the same time, Kennedy’s interest in the developing world was different from his predecessors’ and led him to experiment with new ways of projecting US power internationally, including through building up local capabilities to fight “wars of national liberation.” His national security bureaucracy changed accordingly with the creation of a Special Group on Counterinsurgency, the US Agency for International Development (USAID), the Peace Corps and with a renewed focus on the US Army’s Special Forces.

At the start of 1965, the Johnson administration was primed to act militarily in Vietnam. On the economic front, Secretary of the Treasury Dillon left and Johnson chose his Great Society over fiscal discipline. McNamara began to manipulate the budget to hide the true costs of military escalation. Initially, he staked his hopes on a bombing program: it would ensure civilian control, be cost-effective and quick. When political overtures failed to materialize, however, he became frustrated. In July, McNamara recommended a wholescale escalation with a tax increase and reserve call-up. Johnson chose escalation without aligning the resources to his new commitments. As a result, a rift emerged between the President and his Secretary of Defense. As the year went on, the rift widened and McNamara considered leaving. He grew impatient with the White House and State Department’s inflexibility over negotiations with North Vietnam and threw his weight behind a bombing pause.