The United States has residual responsibility over all former Japanese territories.
美國對所有日本前領土都負有剩餘責任。
Memorandum: Deputy Assistant Secretary of State for Far Eastern Affairs Economic Affairs (Jones)
Date: June 10, 1956
Subject: Paracel Islands, etc.
備忘錄: 遠東事務經濟司副助理國務卿(瓊斯)
日期: 1956年06月10日
主旨: 西沙群島等
During the discussion, the Secretary pointed out that we might consider acting under the Japanese Treaty since the U.S. has residual responsibility over all former Japanese territories.
國務卿在討論中指出,我們可以考慮根據《日本條約》採取行動,因為美國對所有日本前領土仍擁有責任。
[ source: United States Department of State / Foreign relations of the United States, 1955-1957. China, Volume III (1955-1957), page 378 ]
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[中文版本] https://www.twdefense.info/trust3/frusch-1956aq.htm