中美共同防禦條約
As the Korean War broke out, the Truman Administration resumed economic and military aid to the ROC on Taiwan and neutralized the Taiwan Strait by United States Seventh Fleet to stop a Communist invasion of Formosa (as well as a potential ROC counter-invasion of the mainland). US military presence in Taiwan consisted of the Military Assistance Advisory Group (MAAG) and the United States Taiwan Defense Command (USTDC). Other notable units included the 327th Air Division. Until the US formally recognized the People's Republic of China in 1979, Washington provided ROC with financial grants based on the Foreign Assistance Act, Mutual Security Act and Act for International Development enacted by the US Congress. A separate Sino-American Mutual Defense Treaty was signed between the two governments of US and ROC in 1954 and lasted until 1979.