What happened
The United States establishes diplomatic relations with the PRC, de-recognises the ROC and terminates the 1954 Mutual Defense Treaty, while stating that it acknowledges the Chinese position that there is one China and Taiwan is part of it.
Recognition of Beijing removed Taiwan's formal security guarantee and set up the improvised replacement that has governed ever since. The precise wording — "acknowledges" rather than "accepts" — remains actively disputed and is the hinge of most legal argument about US policy.
Confidence: High
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