The Cold War from 1945 to 1980

By the end of this lesson, students will be able to:

• Account for the way the wartime alliance with the Soviet Union dissolved between 1945 and 1947 and explain how George F. Kennan's analysis and the Truman Doctrine produced the strategy of containment.
• Describe the Korean War (1950-1953) as the first hot test of containment, including the role of the United Nations, the 38th parallel, the dismissal of General MacArthur, and the 1953 armistice that froze the peninsula in place.
• Explain Eisenhower's New Look defense policy, the doctrines of massive retaliation and brinkmanship associated with Secretary Dulles, and the strategic shocks of Sputnik (1957) and the U-2 incident (1960).
• Reconstruct the thirteen days of the Cuban Missile Crisis in October 1962 and account for the public and secret terms by which the United States and the Soviet Union stepped back from nuclear war.
• Account for the rise and fall of detente from 1969 to 1979, including SALT I, the Nixon openings to Beijing and Moscow, the Helsinki Accords of 1975, the Soviet invasion of Afghanistan in 1979, and the Carter Doctrine of January 1980.

The Cold War of 1945 to 1980 is the central story of American foreign policy in Period 8 and the dominant pressure on American domestic life across the same thirty-five years. The wartime alliance against Nazi Germany dissolved almost immediately once the common enemy was gone. The Soviet Union refused to withdraw from the territory the Red Army had liberated in Eastern Europe; Stalin installed friendly governments in Poland, Hungary, Romania, Bulgaria, and Czechoslovakia; and by the spring of 1946, when Winston Churchill named the dividing line an "iron curtain" in his Fulton, Missouri address, the bipolar world of the next four decades had taken its rough shape. American policymakers committed the country to the strategy that would organize their response to that world: containment, the prevention of further Soviet expansion through economic aid, collective-security pacts, and military commitments around the perimeter of the communist bloc (KC-8.1.I, KC-8.1.I.A).

Containment had two intellectual fathers. George F. Kennan, the State Department's senior Soviet specialist, set out the theory in his February 1946 "Long Telegram" from Moscow and again, anonymously, in his July 1947 Foreign Affairs article signed Mister X. Soviet expansion, Kennan argued, was driven by ideology and would yield only to long, patient, firm, and vigilant counter-pressure at every point along the perimeter of the Soviet bloc. President Truman gave the strategy its public form. In his March 12, 1947 address to a joint session of Congress, asking for four hundred million dollars in aid to Greece and Turkey, Truman pledged that the United States would support free peoples resisting subjugation by armed minorities or by outside pressures (KC-8.1.I.A). The Truman Doctrine was followed within months by the Marshall Plan, roughly thirteen billion dollars to rebuild the war-shattered economies of Western Europe; the Berlin Airlift of 1948-1949, which broke a Soviet blockade of the western sectors of the divided city; and the North Atlantic Treaty of April 1949, which bound the United States to the defense of Europe in the first peacetime alliance the country had ever signed. National Security Council Report 68 (NSC-68), drafted in April 1950, took the doctrine to its strategic conclusion: the United States would underwrite a massive peacetime military establishment to deter Soviet expansion globally.

NSC-68 was completed eight weeks before North Korean forces crossed the 38th parallel on June 25, 1950 and turned containment into a hot war. The Korean War ran from 1950 to 1953 and is the first major test of the new strategy (KC-8.1.I.B.i). Truman secured a United Nations mandate to defend South Korea while the Soviet Union was boycotting the Security Council; American and allied troops, fighting under United Nations command, pushed back from the Pusan Perimeter after General Douglas MacArthur's amphibious landing at Inchon in September 1950 and drove north past the 38th parallel toward the Yalu. The intervention of roughly three hundred thousand Chinese "volunteers" in late October produced a long retreat and a war of attrition along the original frontier. MacArthur's public demands for an expanded war against China produced the most consequential civil-military confrontation of the postwar era; Truman dismissed him in April 1951 in defense of the principle that elected civilians, not generals, set foreign policy. The armistice of July 1953, signed at Panmunjom, froze the peninsula along a line close to the 38th parallel. The peninsula remained divided and technically still at war into the present.

Korea reshaped the American Cold War. Defense spending tripled; the United States stationed troops permanently in West Germany and South Korea; and a Republican president elected in 1952 on a promise to end the war set out to deliver Cold War security at lower cost. Dwight D. Eisenhower's New Look defense policy trimmed conventional ground forces, enlarged the strategic nuclear arsenal and the bomber fleet of the Strategic Air Command, and assigned a larger covert role to the Central Intelligence Agency in places such as Iran (the 1953 coup against Mohammad Mossadegh) and Guatemala (the 1954 coup against Jacobo Arbenz). Secretary of State John Foster Dulles announced in January 1954 that the United States would rely on a capacity for massive retaliation, instantly and at places of its own choosing. Critics named the diplomatic style that followed brinkmanship: a willingness to walk to the edge of nuclear war to extract Soviet concessions. The doctrine produced strategic stability of a kind, and it produced two strategic shocks that the Eisenhower administration could not contain.

The first shock came in October 1957, when the Soviet Union launched Sputnik 1, the first artificial satellite. The launch was a propaganda triumph and a strategic warning: a rocket capable of placing a satellite into orbit could deliver a thermonuclear warhead to any city in the United States. Congress responded with the National Aeronautics and Space Act of 1958 and the National Defense Education Act of the same year, which poured federal money into university science, mathematics, and foreign-language programs. The Space Race followed within months. The second shock came in May 1960, when a Soviet surface-to-air missile shot down an American U-2 reconnaissance aircraft over the Urals. Pilot Francis Gary Powers parachuted into Soviet captivity; the cover story collapsed at the Paris summit; and the sober public recognition that both superpowers were now a missile-launch away from each other helped elect John F. Kennedy in November 1960 on the false premise of a "missile gap" that favored Moscow.

Kennedy inherited the Cold War at its most dangerous edge. The Bay of Pigs invasion of April 1961, an Eisenhower-era CIA plan to land Cuban exiles on the south coast of Cuba and topple Fidel Castro, collapsed within seventy-two hours and handed Castro and the Soviet Union a public propaganda victory. In August 1961 the East German government, with Soviet approval, sealed the boundary between East and West Berlin and began construction of the Berlin Wall, which would stand until 1989 as the most visible monument of the Cold War in Europe. Fourteen months later, in October 1962, the Cold War came as close to nuclear war as it would ever come. American U-2 photography on October 14, 1962 revealed Soviet medium- and intermediate-range ballistic missile sites under construction in Cuba, ninety miles from Florida. For roughly thirteen days the world held its breath.

The Cuban Missile Crisis ran from October 16, 1962, when Kennedy was first briefed, through October 28, 1962, when Soviet Premier Nikita Khrushchev publicly agreed to dismantle the missile sites. Kennedy's response combined a naval quarantine of Cuba (announced on October 22 in a televised address), a public ultimatum, and quiet diplomacy. The crisis ended with two understandings. The public deal was that the Soviet Union would withdraw the missiles in exchange for an American pledge not to invade Cuba. The secret deal, negotiated through Robert Kennedy and Soviet Ambassador Anatoly Dobrynin, was that the United States would, after a face-saving interval, withdraw its Jupiter intermediate-range ballistic missiles from Turkey. Khrushchev was deposed two years later, partly for accepting the trade. Kennedy was assassinated in November 1963. The two governments had stared at each other across the edge of nuclear war and stepped back. The aftermath produced the Moscow-Washington hotline (1963), the Limited Test Ban Treaty (1963), and a sober new appreciation in both capitals of how easily a Cold War standoff could escalate into mutual destruction.

The crisis also accelerated a slow Soviet-American search for stable rules. By the time Richard Nixon entered the White House in January 1969, the Vietnam War, the splitting of the communist bloc into Soviet and Chinese halves, the rough nuclear parity reached during the 1960s, and the cost of a global commitment all argued for a new posture. Nixon and his National Security Adviser Henry Kissinger called it detente: a deliberate relaxation of Cold War tensions that aimed to manage the rivalry rather than to win it. Three monuments mark the policy. In February 1972 Nixon flew to Beijing for an eight-day visit that ended twenty-three years of formal nonrecognition between the United States and the People's Republic of China. In May 1972 Nixon flew to Moscow and signed the Strategic Arms Limitation Treaty (SALT I), the first agreement to cap the number of intercontinental and submarine-launched ballistic missiles each side could field, paired with the Anti-Ballistic Missile Treaty that froze missile-defense deployment. In August 1975, at Helsinki, thirty-five states (the United States, the Soviet Union, Canada, and every European state except Albania) signed a Final Act that recognized the postwar borders of Europe and committed all parties to a baseline of human rights, including the free movement of people and information. The Helsinki human-rights provisions, intended by Moscow as a concession of words, became the legal lever that East European dissidents and the Carter administration would use against the Soviet bloc through the rest of the decade.

Detente was already fraying when, on Christmas Day 1979, Soviet airborne forces seized Kabul. The Soviet invasion of Afghanistan, intended to prop up a faltering communist government and prevent an Islamist takeover on the southern flank of the Soviet Union, ended detente as a working policy. President Jimmy Carter withdrew SALT II from the Senate, embargoed grain shipments, and called for an American boycott of the 1980 Moscow Summer Olympic Games. In his State of the Union address of January 23, 1980, Carter announced what the press immediately named the Carter Doctrine: any attempt by an outside force to gain control of the Persian Gulf region would be regarded as an assault on the vital interests of the United States and would be repelled by any means necessary, including military force. The doctrine, framed against the Soviet army in Afghanistan and the Iranian revolution that had toppled the shah a year earlier, committed the United States to the long, expensive defense of the Middle East oil flow that Period 9 would inherit. By 1980, when the period closes, the United States was rebuilding the defense budget Carter had begun and would arm the Afghan mujahideen against Soviet occupation in a covert war that ran for the next decade. The arc of the Cold War from Truman to Carter is the arc this lesson asks students to reconstruct (KC-8.1.I.A, KC-8.1.I.B.i, KC-8.1.I.C).

The four excerpts below mark the four hinge moments of the Cold War in Period 8: the doctrine that opened it, the brinkmanship that set its strategic edge, the moment it almost ended in nuclear war, and the doctrine that closed Period 8 by reorganizing American commitments around the Persian Gulf.

1. (Causation) Trace the causal chain from the dissolution of the wartime alliance with the Soviet Union in 1945 and 1946 to the formal commitment of the Truman Doctrine in March 1947. At which step in the chain do you think a different decision could have produced a different outcome, and why?
2. (Continuity and Change) Compare the containment strategy as Truman practiced it (1947-1953) with the New Look version Eisenhower and Dulles practiced (1953-1961). Identify two continuities and two significant shifts. Which set is more historically consequential?
3. (Causation) Account for how the Cuban Missile Crisis ended without a nuclear exchange. What weight do you give the public quarantine, the secret Jupiter-missile trade, the Khrushchev-Kennedy back-channel correspondence, and the willingness of both leaders to accept domestic political costs to step back?
4. (Comparison) Compare detente under Nixon and Kissinger (1969-1974) with the harder anti-Soviet line that returned under Carter after December 1979. What does the comparison reveal about the relationship between superpower competition and domestic political pressure?
5. (Continuity and Change) The Helsinki Accords of 1975 recognized postwar European borders that the United States had refused to recognize for thirty years. Was Helsinki a Soviet diplomatic victory, an American moral victory through the human-rights provisions, or both at once? Defend a clear claim with specific evidence.

Draft alignment — pending educator review. AP USH codes correspond to the official College Board Course and Exam Description (Effective Fall 2023, Version 1). Statements below are paraphrased in the CountryReports voice; refer to the College Board's published CED for verbatim wording.