U.S. has already accepted "common heritage of mankind" principle in previous agreements and domestic law
U.S. is bound to the "common heritage of mankind" principle through customary international law as it has accepted it in numerous previous treaties and has even included it in domestic seabed mining legislation.
Quicktabs: Arguments
However, the United States is likely already bound by the “common heritage of mankind” doctrine under principles of customary law.61 Customary law is generally thought of as widespread systematic practice that is backed by opinio juris, or the belief that one is acting in accordance with legal obligation.62 Because these are not objectively measureable qualities, customary law is not always easy to identify. The Convention, including its provisions regarding the “common heritage of mankind” principle, is considered to represent the customary law of the seas, supported in part by its widespread ratification.63 Under general principles of international law, customary law is binding on all states, including the United States.64 The United States, thus, is bound by those provisions of the Convention that are deemed customary law, which likely include the “common heritage of mankind” principle.
Additionally, the United States explicitly acknowledges the “common heritage of mankind” principle in its passage of the Deep Seabed Hard Mineral Resources Act.65 The Deep Seabed Hard Mineral Resources Act notes that deep seabed minerals are the “common heritage of mankind” and establishes a temporary framework for the responsible and respectful mining of the deep seabed taking into account the interests of other nations.66 That the Deep Seabed Hard Mineral Resources Act was intended as a temporary framework until the Convention could be agreed upon and ratified67 further supports the United States’ willingness to embrace the “common heritage of mankind,” and ultimately the Convention which incorporates this principle.