<p>The flaw in massive retaliation was obvious. A factory worker in Indiana, raising a family in a home purchased with his veterans' benefits, might go back into uniform and fight if anybody threatened his wife and children, but wasn't too aroused by what the Soviets were doing with Patrice Lumumba. Furthermore, if the US reacted to Soviet meddling in some African backwater, Moscow might—in turn—launch its missiles at North America.
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<p>Robert S. McNamara, who served as Defense Secretary under Presidents Kennedy and Johnson (1961-66), changed the nation's strategy (and with it the Air Force's mission) when he spoke of deterrence in a 1962 address at Ann Arbor, Michigan. McNamara cautioned that the US and USSR were like "two scorpions in a bottle." The new policy would be, as McNamara called it, "assured destruction." Others coined the term MAD, for mutually assured destruction.
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<p>Few statements of policy have been more misunderstood. Critics thought McNamara was warning Moscow that the US intended to keep its warheads aimed at Russian cities rather than shifting to purely military targets. In fact, McNamara wanted something very different: to limit the size of the American arsenal.
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<p>MAD was less insane than critics supposed. It meant an opportunity to limit the growth of US nuclear forces by establishing a 'criterion of sufficiency'. Since the United States, and the US Air Force, lacked the resources for a 'numbers' contest with the Russians and could never match Moscow man for man, aircraft for aircraft, missile for missile, Washington could now equip and arm its forces only with enough weaponry to ensure that the Soviet Union would not survive a nuclear exchange. "We won't try to out-build the Russians," Congressman David Murphy promised at the time to a public concerned about military expenditure. "We will only build enough to destroy them."
