"Those who are … beating the drums of war should explain clearly to the American people what they think the costs and benefits would be."

The president had in mind such remarks as those Newt Gingrich delivered to the Israeli lobby AIPAC that same day: "The red line is now … because the Iranians are deepening their commitment to nuclear weapons" — an assertion the Joint Chiefs and U.S. intelligence agencies say is blatantly false.

They insist: Iran has not made the decision to build a bomb.

Perhaps the president was referring to Mitt Romney’s pledge to that same cheering throng to "station multiple carriers and warships at Iran’s door" and deny Tehran even "the capacity to make a bomb."

But if "the capacity to make a bomb" means knowledge of how to build one and an ability to enrich uranium to bomb-grade, should they decide to do so, Iran already has that.