Assad isn’t subject to either of the two authorizations Congress passed after 9/11 to bless the use of military force. He’s not part of al Qaeda, nor a successor organization like the Islamic State—which is dubiously covered under the 2001 authorization as it is—nor is he part of Saddam Hussein’s regime.

The closest Trump aides have come to providing a domestic legal justification for striking Assad, offered by his former secretary of state, is that Trump possesses the inherent authority to do so as commander-in-chief, a gigantic assertion last used—and ultimately abandoned—by George W. Bush’s administration.

The implications are large and ominous, according to a member of the Senate Armed Services Committee. “If [Trump] strikes Syria without our approval, what will stop him from bombing North Korea or Iran?” Sen. Tim Kaine (D-Va.) told The Daily Beast on Tuesday.