I know that many people think that as long as two heads of state sign a document a real deal has been made. Well, it certainly isn't true of the "Joint Understanding" agreed to last week at the Kremlin by the two presidents--Dmitry Medvedev and Barack Obama--with some pomp and even more circumstance.

Charles Krauthammer's Friday Washington Post column explains patiently and persuasively why the so-called nuclear understanding is not even that.

But Obama also tagged some concrete hope on to the document: that the American-Russian mini-transaction would encourage Iran and North Korea to forego their atomic ambitions. I'm afraid I agree with Charles that this assertion is "comical."

Then, on Wednesday morning, came a Reuters dispatch from Moscow:

"Russia Says No Iran Sanctions for START Deal." But Obama aides had said precisely that START would persuade Russia to be more cooperative with the U.S. on sanctions. It took barely a week for Medvedev to disappoint his visitor. If, that is, his visitor will realize that he should be disappointed.