美國可以對台灣提出法律上的要求

In the peace treaty, Japan has merely renounced sovereignty over Taiwan, but there has been no other disposition. The United States also has an interest in Taiwan and could assert a legal claim to the island(s). Hence, the disposition of Taiwan is not merely an internal Chinese problem.
在和平條約中，日本僅是放棄了對台灣的主權，但沒有其他處置。美國在台灣也有權益，可以對台灣提出法律上的要求。因此，台灣的處置不僅僅是中國內部的問題。

Memorandum: The Dept. of State

Date: July 1, 1955

Subject: Lessening of Tension in the Taiwan Area

備忘錄： 美國國務院

日期： 1955年07月01日

主旨： 減輕台灣地區的緊張氣氛

. . . . . Even the juridical position of Taiwan is in doubt. The United States also has an interest in Taiwan which we got away from Japan. Japan has merely renounced sovereignty over Taiwan which has not been disposed of by the peace treaty and not ceded to anyone. Consequently the United States could assert a legal claim until Taiwan is disposed of by some means. [FN #1] We cannot, therefore, admit that the disposition of Taiwan is merely an internal [Chinese] problem.
. . . . . 甚至於台灣的法律地位也受到質疑。美國對台灣也有權益，是我們從日本獲的。日本只是放棄了對台灣的主權，該主權沒有被和平條約處理，也沒有割讓給任何實體政權。因此，在台灣通過某種方式給予 (最終) 處置之前，美國可以提出法律上之要求、請求。[備註 #1] 因此，我們不能承認台灣的處置僅僅是一個 [中國] 的內部問題。

[ source: United States Department of State / Foreign relations of the United States, 1955-1957. China, Volume II (1955-1957), page 619-620 ]

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[FN #1] Editor's note: The huge amount of war resources invested by the United States in World War II (Pacific Theater) had the direct result of achieving the liberation of Taiwan from Japan. Accordingly, the United States is certainly a stakeholder in the future (final) disposition of Taiwan.
[備註 #1] 編輯按：基於美國在第二次世界大戰（太平洋戰區）中投入的鉅額戰爭資源，直接導致台灣從日本獲得解放。是故，美國無疑是台灣未來（最終）處置方式的權益攸關方。