Pactomania

Pactomania is a term originally created to describe the period between 1945 and 1955, during which the United States concluded or ratified a significant amount of alliances, treaties, and pacts. The word "Pactomania" was first used in a The New York Times article in 1955.^[1]

Following World War II, the US abandoned its previous policy of isolationism and embraced internationalism, occupying Japan, southern Korea, and zones in Germany and Austria, hosting the new United Nations, International Monetary Fund, and World Bank, and establishing the US dollar as the world's reserve currency through the Bretton Woods system. In terms of defense, the US initially supported the idea of collective security by the five UN Security Council powers, with the US focused on the defense of its sphere of influence in the Western Hemisphere through the Organization of American States and the multilateral Rio Pact security alliance.^[2][3]

However, growing concerns over the Soviet Union's large military presence and installation of satellite states in Eastern Europe, espionage activities within the US, and the potential for the spread of communism in devastated Europe and decolonizing nations led to a shift in US foreign policy. The inability of the United Kingdom to manage these issues, as evidenced by the Greek Civil War and Turkish Straits crisis, prompted the US to become closely involved in Europe and adopt the Truman Doctrine of containing communism through Marshall Plan financial aid and the multilateral North Atlantic Treaty Organization (NATO) security alliance.

In Asia, the US initially focused on the Acheson Line or "defense perimeter", which did not prioritize China, Korea, or Taiwan.^[4][5] However, the fall of China to communism and the subsequent public outcry in the US led to a change in approach. The US became involved in the Korean War and established a system of bilateral security alliances along the western Pacific Rim, often referred to as the "hub-and-spoke system", including alliances with Japan, South Korea, Taiwan, and the Philippines, as well as Australia and New Zealand.^[6] Additionally, the multilateral Southeast Asia Treaty Organization (SEATO) security alliance was formed in Southeast Asia. The multilateral Middle East Treaty Organization (METO) security alliance, intended to fight communism in the Middle East, ended up never being joined by the United States due to "the pro-Israel lobby".^[7]

The alliances formed during Pactomania have played a pivotal role in the modern era, from the Vietnam War to the Russian invasion of Ukraine.^[8][9] Today, many of the alliances formed during Pactomania remain today, although SEATO, METO, and the US-Taiwan alliance have been dissolved. Despite the dissolution of SEATO, its underlying collective defense treaty remains in force, and forms the basis of the US-Thailand mutual security alliance.^[10] Similarly, in spite of the 1979 dissolution of the US-Taiwan alliance, the US retains significant military relations with Taiwan through the Taiwan Relations Act.