A "valid treaty" would require Senate approval - it did not have that. It was an agreement, and the US was not bound by it after the Taliban violated it. They

A "valid treaty" would require Senate approval - it did not have that. It was an agreement, and the US was not bound by it after the Taliban violated it. They wouldn't have been bound to it in any case, because it was never approved by the Senate. There is no international police force or authority that the president is required to obey. Biden overruled his advisors and pursued this. His hands were not tied. He's proud he took this action, and has stated so many times.