It's really not a crime against the US constitution. And "International Law" isn't really law, because there is no enforcer.
International politics is anarchy. Rules are enforced by the hegemon.
Article I of the Constitution, Section 8: only Congress has the power to declare war.
International law exists - it’s the very purpose of the International Court of Justice
Article I of the Constitution, Section 8: only Congress has the power to declare war.
International law exists - it’s the very purpose of the International Court of Justice