There’s a very revealing quote from Hillary Clinton in the Atlantic article on Obama’s foreign policy:

Right after Obama’s reversal [on attacking Syria], Hillary Clinton said privately, “If you say you’re going to strike, you have to strike. There’s no choice.”

Clinton is dangerously wrong about this, but she was just saying privately what countless others said about the “red line” episode and U.S. “credibility” during and after the Syria debate. This is a very conventional and wrongheaded view of the “necessity” of following through on threats, even if the threatened action is misguided and unnecessary. The assumption behind this is that if the U.S. threatens to “act” (i.e., kill people) in a given situation, it must carry out the threat or else future threats in completely different situations won’t be believed. There is no good reason to believe that this is how anyone judges threats to use force. If the U.S. makes a vague threat to use force in a place where it has little or nothing at stake, that threat isn’t likely to be taken seriously in any case. Refusing to back up such a foolish threat will have no effect on how its threats or formal commitments elsewhere are judged.

More to the point, making an ill-advised threat doesn’t oblige a president to follow through on it if carrying out the threat doesn’t advance U.S. interests. It would be best for a president not to make ill-considered threats, but once he’s done that he isn’t required to stick with a foolish commitment if he subsequently realizes it was foolish. The fact that Clinton thinks “there’s no choice” once a threat has been made is one more reminder that her foreign policy judgment is poor and can’t be trusted.