This remained the situation for three decades: Taiwan and China remained officially at war; the United States continued to support the ROC claim as the legitimate government of all China, refused to recognize the legitimacy of the PRC, and maintained a defense alliance with the ROC government on Taiwan. Official U.S. The Taiwan Relations Act (P.L. 96-8 )—which remains the domestic legal authority for conducting unofficial U.S. relations with Taiwan today. Much of the TRA deals with the logistics of U.S.-Taiwan relations: the establishment of the American Institute in Taiwan (AIT) as the unofficial U.S. representative for diplomatic interactions with Taiwan, including details about its staffing, functions, and funding. Strategic Ambiguity

After normalization of Sino-U.S. relations and the severing of the U.S.-ROC military alliance, the PRC was largely satisfied with U.S. "one-China" formulations alluding to Taiwan's political status. In that communiqué, the PRC cited it had a "fundamental policy" of striving for a peaceful solution to the Taiwan question, while Washington stated that the United States did not: 
seek to carry out a long-term policy of arms sales to Taiwan, that its arms sales to Taiwan will not exceed, either in qualitative or quantitative terms, the level of those supplied in recent years since the establishment of diplomatic relations between the United States and China, and that it intends to reduce gradually its sales of arms to Taiwan. – The Joint Communiqué on the Establishment of Diplomatic Relations Between the United States of America and the People's Republic of China, January 1, 1979 "In the Joint Communiqué [of January 1, 1979]... the United States of America ...acknowledged the Chinese position that there is but one China and Taiwan is part of China.... Given the historical record and with continuing transformations in both the PRC and Taiwan political systems, U.S. officials may be facing new and more difficult policy choices concerning Taiwan in the coming years. Measures introduced in the 111 th Congress as of this writing include: 
A bill establishing diplomatic relations with Taiwan: H.Con.Res. 18 (introduced January 9, 2009, by Representative John Linder); A measure expressing U.S. concern over and support for peaceful resolution to Taiwan's political status: H.Con.Res. 200 (introduced October 15, 2009, by Representative Robert Andrews); A provision funding democracy assistance to Taiwan: in S. 1434 , the Department of State, Foreign Operations, and Related Agencies Appropriations Act for 2010 (introduced July 9, 2009); And a provision requiring the Pentagon to assess and submit a report on the capabilities of Taiwan's air force and a five-year plan for fulfilling U.S. defense obligations to Taiwan under the Taiwan Relations Act: in S. 1390 , the National Defense Authorization Act for FY2010 (introduced July 2, 2009).
In 1979, official U.S. relations with Taiwan (the Republic of China) became a casualty of the American decision to recognize the government of the People's Republic of China (PRC) as China's sole legitimate government. Since then, U.S. unofficial relations with Taiwan have been built on the framework of the Taiwan Relations Act (P.L. 96-8) and shaped by three U.S.-China communiqués. Under these agreements, the United States maintains its official relations with the PRC while selling Taiwan military weapons and having extensive economic, political, and security interests there. But developments in both the PRC and Taiwan political systems mean U.S. officials continually are facing new policy choices. These developments include ongoing transformations in both Taiwan's and the PRC's political systems, economic and trade cycles and, in 2008, a renewal of contacts, talks, and agreements between the two sides.
This report is intended as a background overview of the historical and political complexity associated with Taiwan's status in the world and its continuing policy ramifications. In brief, this report discusses the civil war on China in the 1940s that resulted in the victory of communist forces and the ROC government's flight to Taiwan; reviews the Taiwan government's continued recognition as the sole government of China by much of the world and the United States until 1979; and discusses the Taiwan government's eventual loss of diplomatic relations with the United States and with all but a handful of countries. The report further discusses how the United States handles its extensive ongoing economic and security interests in Taiwan in the absence of official relations, and places in context the recurring policy complications that these interests pose for U.S. relations with the PRC. This report lays out the background and framework that affect how U.S. relations with both Taiwan and China are conducted today. This report will not be updated, and readers wishing to follow current policy issues involving Taiwan and China should consult other regularly updated CRS reports. As of the date of this report, these include CRS Report R40493, Taiwan-U.S. Relations: Developments and Policy Implications; and CRS Report RL30957, Taiwan: Major U.S. Arms Sales Since 1990.
Relevant legislation introduced in the 111th Congress as of the date of this report includes a measure that would establish diplomatic relations with Taiwan (H.Con.Res. 18, introduced January 9, 2009); a measure expressing U.S. concern over and support for peaceful resolution to Taiwan's political status (H.Con.Res. 200, introduced October 15, 2009); a provision funding democracy assistance to Taiwan (in S. 1434, the Department of State, Foreign Operations, and Related Agencies Appropriations Act for 2010, introduced July 9, 2009); and a provision requiring the Pentagon to assess and submit a report on the capabilities of Taiwan's air force and a five-year plan for fulfilling U.S. defense obligations to Taiwan under the Taiwan Relations Act (in S. 1390, the National Defense Authorization Act for FY2010, introduced July 2, 2009).