Robert S. McNamara (1916-2009) is best known for his role as Secretary of Defense (January 21, 1961 - February 29, 1968) in the Administrations of John F. Kennedy and Lyndon B. Johnson. He was a key architect of the overt combat role of the United States in the Vietnam War, although he lost confidence in U.S. policy and resigned from the Johnson Administration, and was named President of the World Bank.
McNamara built his reputation as a specialist in statistically-based management. His undergraduate degree, from the University of California at Berkeley was in in economics and philosophy, and then earned a Master of Business Administration from Harvard Business School. After a year in a public accounting firm, he returned to the Harvard Business School, teaching from 1940 to joining the Army Air Forces in 1943 as a captain.
While in uniform, he gathered a team of statisticians, economists, and other quantitative management specialists, in part practicing the not-yet-named discipline of operations research. Reaching the rank of lieutenant colonel, he and his colleagues offered their services, as a group informally called the "whiz kids", to various businesses. He joined Ford Motor Company as manager of planning and analysis, rising to company president in 1960. He was the first president who was not a member of the Ford family, and his differences from most Ford executives were significant; he lived in the Michigan suburb and academic area of Ann Arbor rather than the traditional executive area of Grosse Pointe, and did not participate in the usual Ford or community social life.
Nominally a Republican, he was appointed as Secretary of Defense less than five weeks after becoming president at Ford. Among the conditions he required before accepting the post was a guarantee of not having to participate in political and social events, and that he could bring some of his key associates, notably the economist, Alain Enthoven. Enthoven was placed in the newly created position of Assistant Secretary of Defense for Systems Analysis.
Basis of decisionmaking
He was a strong believer in his concept of civilian control of the military, which extended far beyond the usual policy level of previous Secretaries; only Donald Rumsfeld, among subsequent Secretaries, may have been as detailed a manager. McNamara was quite willing to overrule the uniformed military on operational matters and decisions involving weapons system selection. Cost-effectiveness and systems analysis were his credos, with mixed results. One notable failure was insistence on a tactical aircraft, the F-111, which would be common, only with some variations, to the United States Air Force and United States Navy. The Air Force version, the F-111A, eventually became an effective fighter-bomber, and continued to be upgraded into a variety of roles, with its electronic warfare variant being retired in the 1990s. The Navy F-111B, however, never became operational.
In general, he assumed that opponents were fully rational actors, and would make decisions based on the same sort of quantitative methods he would use. Military officers that brought up issues of motivation and morale, and fighting for ideology, tended to be treated with disdain.
His approach was probably most effective in nuclear policy.
With Kennedy, he rejected massive nuclear retaliation as the basis of U.S. military policy. The idea of flexibility in nuclear response actually started when Dwight D. Eisenhower, in 1959, asserted his authority over the largely autonomous Strategic Air Command; Eisenhower's initiative, managed by presidential science advisor George Kistiakowsky, led to the first set of nuclear war plans that both reflected civilian national policy, and also coordinated the nuclear delivery systems of all the military services. The first Single Integrated Operational Plan (SIOP) was made official in 1962, and the basic concept of the exceptionally highly classified plan has continued ever since.
This is not to suggest that McNamara did not personally take a major role in nuclear strategy, and his concept of a rational actor may indeed have been relevant to what became the strategy of Mutual Assured Deterrence (MAD). MAD required that a credible nuclear force be able to survive any possible Soviet attack, and he put considerable emphasis on command and control systems that would function under attack, as well as techniques to ensure weapons system survival, including airborne bomber patrols, intercontinental ballistic missiles in hardened underground silos, and essentially undetectable submarine-launched ballistic missiles. This deterrent may, indeed, have restrained the Soviets during the 1962 Cuban Missile Crisis.
Both Kennedy and McNamara were advocates of a wide range of ways to apply national power. A major goal was to counter Communist "wars of national liberation," in which the enemy avoided head-on military confrontation and resorted to political subversion and guerrilla tactics. As McNamara said in his 1962 annual report, "The military tactics are those of the sniper, the ambush, and the raid. The political tactics are terror, extortion, and assassination." This meant building U.S. capabilities for unconventional warfare, United States Army Special Forces and other nontraditional military units and techniques, further alienating McNamara from the senior professional military. While some of these tactics were effective in the Vietnam War, it is also accepted that McNamara micromanaged military decisionmaking without substantive knowledge of the subject. While Kennedy may have started U.S. involvement in Southeast Asia, it was Lyndon Johnson, on the advice of McNamara, that turned it into a major war. There is considerable evidence that Johnson and McNamara manipulated the Congress and public. 
In particular, McNamara insisted on a signaling strategy in gradual application of military power to North Vietnam. Key contributors to his thinking included Assistant Secretary of Defense for International Security Affairs, John McNaughton, a law professor before coming to the Defense Department as the senior official for politicomilitary policy. McNamara also drew inspiration from the compellence strategy developed by the economist, Thomas Schelling.  For the first years of the war, he was convinced that the North Vietnamese leadership would decide that they were taking unacceptable damage and stop their aggression; he dismissed the Maoist concept of protracted war, and the idea that the other side was quite willing to take what he considered unacceptable losses.
By the time Johnson took office, there was already a significant U.S. involvement in Vietnam, although large-scale combat forces had not been committed. McNamara, who had been appointed by Kennedy, continued to push an economic and signaling grand strategy to Johnson. Johnson and McNamara, although it would be hard to find two men of more different personality, formed a quick bond. McNamara appeared more impressed by economics and Schelling's compellsnce theory than by Johnson's liberalism or Senate-style deal-making, but they agreed in broad policy.
His 1995 book, In Retrospect, spoke of his guilt over unwise decisionmaking in the Vietnam War. He said Averell Harriman agreed, in 1966, the North Vietnamese would never surrender, and the U.S. must accept a coalition government.
In 1997, he went to Hanoi to discuss ways in which the war could have been prevented or limited; his counterpart was Nguyen Co Thach.
- U.S. Department of Defense, Robert S. McNamara
- McMaster, H.R. (1997), Dereliction of Duty : Johnson, McNamara, the Joint Chiefs of Staff, and the Lies That Led to Vietnam, HarperCollins, ISBN 0060187956
- Carlson, Justin, "The Failure of Coercive Diplomacy: Strategy Assessment for the 21st Century", Hemispheres: Tufts Journal of International Affairs
- Robert S. McNamara (1995), In Retrospect: The Tragedy and Lessons of Vietnam, Time Books/Random House
- McNamara, p. 300