The following is the June 26, 2019 Congressional Research Service In Focus report, Taiwan: Select Political and Security Issues.
From the report
Taiwan, which officially calls itself the Republic of China (ROC), is an island democracy of 23.6 million people located across the Taiwan Strait from mainland China.
Since January 1, 1979, U.S.-Taiwan relations have been unofficial, a consequence of the Carter Administration’s decision to establish diplomatic relations with the People’s Republic of China (PRC) and break formal diplomatic ties with self-ruled Taiwan, over which the PRC claims sovereignty. The Taiwan Relations Act (TRA, P.L. 96-8; 22 U.S.C. 3301 et seq.), enacted on April 10, 1979, provides a legal basis for this unofficial bilateral relationship. It also includes commitments related to Taiwan’s security.
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