Congress would be telling the President to pull all U.S. military forces out of Lebanon within one week of this measure passing. It relies on a law called the War Powers Resolution, which lets Congress force an end to U.S. military involvement somewhere without needing the President's sign-off. In practice, this would affect any U.S. troops currently stationed or operating in Lebanon, who would have to withdraw on that tight timeline, and it would limit the President's ability to keep forces there on his own authority.