Influenced by American society's fear of communism and the containment beliefs of people like George Kennan, who advocated that the United States should use diplomatic, economic, and military action to contain the communism, Truman established the Truman Doctrine, which stated that the United States would protect democracies around the world, pledging to fight them everywhere. This doctrine was an extension of both the Monroe Doctrine and the Roosevelt Corollary. When it came to foreign policy, Truman did everything he could to protect nations against communism, such as the Berlin Airlift, during which Truman decided to avoid the Soviet blockade of West Berlin and deliver supplies directly to the people in need. In Asia, Truman decided to resort to limited war, that is, the absence of atomic weapons, and was strongly criticized by Douglas MacArthur, commander of the army, whom he later fired for not having followed American policy. Eisenhower's dynamic conservatism, now known as Modern Republicanism, was called "Modern Republicanism." as a nonpartisan leader, fiscally conservative in reducing federal spending, and socially moderate in maintaining existing New Deal social and economic legislation. With Secretary of State John Foster Dulles' change in policy, foreign policy toward communism shifted from containing it to rolling back it. Strategic Air Command was created as a fleet of nuclear-armed super-bombers that would enable massive retaliation in place of a large standing army or navy, and the threat of massive retaliation was used to get the Soviets to surrender, and issued Mutual Assured Destruction, where both sides knew that neither nation would declare a nuclear war as it would result in total annihilation...... middle of paper ...... Attack Cuban with total nuclear retaliation. In response to the increase in the number of Soviet ships carrying weapons, JFK ordered a blockade, which he called quarantine because a blockade is an act of war, around Cuba. For 13 days, the world held its breath as the threat of nuclear war loomed over the world, but the Soviets eventually backed down and Khrushchev agreed to remove Cuba's weapons in exchange for no American invasion of Cuba. Meanwhile, in Berlin, the city was in turmoil between the East (Soviet) and the West (controlled by the United States). In order to stop the mass exodus of East Berliners, construction of the 90-mile Berlin Wall began. Both Kennedy and Khrushchev sought ways to ease tensions between the two groups, establishing a direct line between the White House and the Kremlin, which later led to the Limited Ban Treaty, which banned nuclear testing in the atmosphere..