By the dawn of the 1960s, the Cold War was more than a decade old. Neither the containment doctrine of the Democratic Truman administration (1945-53) nor the "massive retaliation" policy of the Republican Eisenhower government (1953-61) had brought the United States close to victory over the Soviet Union. At the same time, neither had allowed Soviet Communists to conquer the globe, either. A tense stalemate was the order of the day.
In 1960, liberal Democratic Senator John F. Kennedy ran for president as a staunch Cold Warrior, promising to escalate America's global competition with the Soviets. Taking advantage of public fears that the US might be losing the Cold War, Kennedy positioned himself to the right of Republican World War II hero Dwight Eisenhower by building his campaign around a promise to close the "missile gap" that Eisenhower had supposedly allowed the Soviets to build up. (In fact, there was no "missile gap"; the US possessed always possessed several times as many nuclear missiles as their Soviet rivals. But the fake "missile gap" issue made for good politics, and Kennedy ran with it.) Kennedy's image as a tough but idealistic foe of Communism helped him to win the 1960 election by the narrowest of margins over Eisenhower's vice president, Richard Nixon.
In his inaugural address, Kennedy used soaring rhetoric to stake out a strong anticommunist position: "Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe, in order to assure the survival and the success of liberty." Kennedy asked his countrymen to support his assertive but principled anticommunist vision, calling upon Americans to "ask not what your country can do for you; ask what you can do for your country."
Kennedy's muscular and idealistic anticommunist policy soon ran aground, however, in Cuba. A year before Kennedy took office, the Caribbean island—located just 90 miles off the coast of Florida—became the scene of a socialist revolution led by Fidel Castro. Castro, a charismatic young leftist, led a ragtag band of guerilla fighters to victory over the unloved Cuban dictator, Fulgencio Batista. While Castro antagonized and infuriated the traditional Cuban elite (many of whom soon fled to Florida), he won the affection and enthusiasm of a large majority of the impoverished Cuban people. The troubling popularity of the left-wing Castro regime presented a major problem to Kennedy's idealistic anticommunist vision; if the Cuban people supported Castro, could the United States then crush Castro's pro-Communist regime without betraying the principle of self-determination that Americans traditionally promised to defend?
Perhaps underestimating Castro's popularity in Cuba, Kennedy chose to seek his overthrow. Only a few months after becoming president, Kennedy authorized a CIA-organized force of anti-Castro Cuban exiles to invade Cuba. The ill-fated invaders landed at a place called the Bay of Pigs, where Castro's forces were waiting to crush them. The invasion failed to topple Castro's government and only strengthened his mystique among the Cuban people. The botched Bay of Pigs Invasion was a huge embarrassment to the United States; Kennedy took full responsibility for the debacle, but the defeat tarnished his reputation, making him appear both inept and unprincipled on the world stage.
A year later, events in Cuba again plunged the Kennedy administration—and this time the entire world—into crisis. When an American spy plane snapped pictures of Soviet troops installing nuclear missiles> in Cuba, Kennedy publicly demanded their immediate removal and ordered a naval blockade of the island. Though his military advisers recommended on several occasions that Kennedy launch air strikes against the missile installations—air strikes which we now know would have almost certainly have led to nuclear war—Kennedy frantically pursued a strategy of negotiation with Soviet Premier Nikita Khrushchev. For thirteen long, tense days, the two great superpowers faced off in stalemate. Never before or since has the world teetered so close to nuclear apocalypse. The crisis finally ended when Kennedy and Khrushchev made a secret deal; in exchange for the Soviets backing down and withdrawing their missiles, the United States would remove its own nuclear missiles from Turkey and promise not to invade Cuba.
The near-death experience of the Cuban Missile Crisis spooked everyone, prompting a general shift in American policy away from directly challenging core Soviet interests. Soviet-American competition shifted to nonviolent venues (the space race and the Olympic games) or to peripheral areas of the world (Southeast Asia, the Middle East, southern Africa), where allies of the two superpowers fought each other in "proxy wars." These conflicts were certainly important (and tragically deadly), but they did not threaten the very existence of either the Soviet Union or the United States.
One of those proxy wars, in Vietnam, convulsed American society in the 1960s and destroyed the presidency of Kennedy's successor, Lyndon B. Johnson. Johnson's Vietnam-induced decision not to run for reelection in 1968 opened the door for the return of Kennedy's old foe from the 1960 election, Republican Richard Nixon. Nixon, like Kennedy, was a committed anticommunist. In fact, virtually his entire political had been built upon the reputation Nixon built as a crusading Communist-hunter during the Red Scare years of the late 1940s and early 1950s. As president, however, Nixon followed in Kennedy's post-Cuba footsteps by pursuing more moderate and nuanced policies towards the Soviet Union. Influenced by his powerful National Security Adviser, Henry Kissinger, Nixon came to see the Cold War as something more complex than a simple bipolar struggle between the US and USSR. Instead, Nixon embraced a multipolar world order in which Soviet and American interests would also be balanced by other nations. By cultivating relationships with other powerful nations—Communist China, Japan, France, Britain, Egypt—the United States could secure its global position.
The result was the Nixon/Kissinger policy of détente (a French word meaning "lessening of tension"), which by 1975 seemed to offer a future of mostly-peaceful coexistence between the superpowers. (In fact, the Cold War soon heated back up; by the 1980s détente was largely abandoned and confrontation once again became the order of the day.)
In retrospect, we can see the Kennedy-to-Nixon era as the "middle period" of the Cold War, falling after the uncertain early stages of the Truman/Eisenhower era but before the renewal of Soviet-American hostilities in the Carter/Reagan years. In this middle period, the clear historical trajectory (after the Cuban Missile Crisis) was away from confrontation and toward détente. In the Kennedy/Nixon era, American and Soviet leaders stared into the abyss of nuclear holocaust and chose to step back from the precipice.