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A defense pact (Commonwealth spelling: defence pact) is a type of treaty or military alliance in which the signatories promise to support each other militarily and to defend each other. [1] Generally, the signatories point out the threats and concretely prepare to respond to it together. [2]
| Year | Treaty name | Member States | 
|---|---|---|
| 1778–1798 | Treaty of Alliance | 
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| 1873–1887 | League of the Three Emperors | |
| 1950–1979 | Sino-Soviet Treaty of Friendship, Alliance and Mutual Assistance | |
| 1954–1977 | Southeast Asia Treaty Organization | 
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| 1955–1979 | Middle East Treaty Organization | 
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| 1955–1980 | Sino-American Mutual Defense Treaty | |
| 1955–1991 | Warsaw Pact | 
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