In 1903, Panama ceded its sovereign rights over the Panama Canal to the United States in perpetuity. The 1930 London Naval Treaty required submarines to comply with the contemporary law of war, including the prohibition on neutralizing enemy merchant vessels without having first ensured the safety of their passengers and crew. In 1945, the United Nations Charter prohibited its members from threatening or using force against another state, save for two limited exceptions. And, in 1969, Spain and Morocco concluded a permanent fisheries convention, setting the limit of their territorial seas at twelve miles.
Change Without Consent: How Customary International Law Modifies Treaties,
Yale J. Int'l L.
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