What part of the US Constitution does it mention treaty?

Answer 1

• Article I, Section 10: No state shall enter into any Treaty, Alliance, or Confederation...

• Article II, Section 2: [The President] shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur.

• Article III, Section 2: The judicial Power shall extend to all Cases, in Law and Equity,arising under this Constitution, the Laws of the United States, and Treaties made, or which shall be made, under their Authority.

• Article VI: ...all Treaties made, or which shall be made, under the Authority of the United States, shall be thesupreme Law of the Land.

Answer 2

Article II of the Constitution provides for all the powers of the President. Under Section 2 of that article, the President is given the power to make treaties, though this is supposed to be done with the advice and consent of the Senate and the treaty does not become law until it has been approved 2/3 of the Senate.

An approved treaty has the force of a law approved by Congress and therefore governs all the states as well (Article VI, last paragraph). The states are specifically prohibited from making treaties on their own in Article 1, Section 10 of the Constitution.