Trump has not withdrawn from the Iran nuclear deal. He has caused the United States to breach it. Here’s why...
The Supremacy Clause of the US Constitution provides that “This Constitution ... and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land”.
The UN Charter is a “treaty” and if validly ratified is the supreme law of the land.
The UN Charter was validly and overwhelmingly ratified in 1945 in accordance with the Constitution.
The UN Charter is therefore the Supreme Law of the Land.
Article 25 of the UN Charter makes UN Security Council Resolutions binding on all member states, including the United States.
UN Security Council Resolution 2231 “Calls upon” member states to support and implement the Joint Comprehensive Plan Of Action (ie, the Iran nuclear deal).
The phrase “Calls upon” is a directive on all member states, including the United States.
The Iran nuclear deal is therefore binding on the United States and all UN member nations in accordance with its terms.
It’s a question of law. And it’s a question of honor.