Excerpt from p. 616
[T]he People's Republic of China in September 1954 initiated artillery shelling against the offshore islands held by the Nationalists. In the midst of the crisis, the United States and the Republic of China signed a mutual defense treaty, in December 1954, by which the United States committed itself to the defense of Formosa and the Pescadores and "such other territories as may be determined by mutual agreement." Mindful of controversies over the legal status of Formosa and the Pescadores, the United States Senate in ratifying the mutual defense treaty noted that "nothing in the present treaty shall be construed as affecting or modifying the legal status or the sovereignty" of Formosa and the Pescadores. (FN: 58)
(58) SENATE COMM. ON FOREIGN RELATIONS, MUTUAL DEFENSE TREATY WITH REPUBLIC OF CHINA, S. EXEC. REP. No. 2, 84th Cong., 1st Sess. 6 (1955).