“Jus cogens may, therefore, operate to invalidate a treaty or agreement between states to the extent of the inconsistency with any such principles or norms.”
“The crime of piracy is considered a breach of jus cogens, a conventional peremptory international norm that states must uphold.”
“In suits alleging violations of a jus cogens norm, however, the facts rarely, if ever, support the claim that an actual waiver arose.”