A defense pact (or defence pact in Commonwealth spelling) is a type of treaty or military alliance in which the signatories promise to support each other militarily and to defend each other. In general, the signatories point out the threats in the treaty and concretely prepare to respond to it together. Current treaties China 1961: Sino-North Korean Mutual Aid and Cooperation Friendship Treaty – mutual defense treaty with North Korea Russia 1992: Collective Security Treaty – established the Collective Security Treaty Organization that also includes Armenia, Belarus, Kazakhstan, Kyrgyzstan, and Tajikistan United Kingdom 1949: North Atlantic Treaty (Treaty of Washington) – establishes NATO mutual defense organization 1958: US–UK Mutual Defence Agreement 1971: Five Power Defence Arrangements 2021: AUKUS - mutual defense alliance between Australia, United Kingdom, and the United States United States 1947: Inter-American Treaty of Reciprocal Assistance (Rio Treaty) – establishes Western Hemisphere mutual defense organization 1949: North Atlantic Treaty (Treaty of Washington) – establishes NATO mutual defense organization 1951: Mutual Defense Treaty Between the United States and the Philippines – mutual defense treaty with the Philippines 1951: ANZUS – mutual defense alliance between Australia, New Zealand, and the United States 1953: Mutual Defense Treaty Between the United States and the Republic of Korea – mutual defense treaty with South Korea 1958: US–UK Mutual Defence Agreement. 1960: Treaty of Mutual Cooperation and Security Between the United States and Japan – mutual defense treaty with Japan 1979: Taiwan Relations Act – contains components of the former Sino-American Mutual Defense Treaty between Taiwan and the United States 2021: AUKUS – mutual defense alliance between Australia, United Kingdom, and the United States Historical treaties Russia 1881: League of the Three Emperors – between the German Empire, Austria-Hungary, and the Russian Empire 1955: Warsaw Pact – between Albania, Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, Romania, and the Soviet Union United Kingdom 1955: Middle East Treaty Organization – between Iran, Iraq, Pakistan, Turkey, and the United Kingdom United States 1778: Treaty of Alliance – between the Kingdom of France and the United States 1954–1977: Southeast Asia Treaty Organization – between Australia, France, New Zealand, the Philippines, Thailand, Pakistan, the United Kingdom, and the United States 1955: Sino-American Mutual Defense Treaty – between China and the United States References Defense Military alliances Treaties by type