Unless in the next week or so he discovers a heretofore unrealized capacity to move public opinion on substantive matters of policy, the expedient thing for lawmakers of either party to do will be to vote “no” while smugly minimizing the moral stakes by noting that while Assad is of course “a bad guy,” he poses no imminent and direct threat to the United States, the Syrian economy is in shambles, there are lots of other mass-murdering dictators and we can’t bomb ’em all, and so forth.
Any opportunistic lawmaker who takes that path will be following the example set by the man who is now president of the United States.