Sooner or later it is going to occur to Barack Obama that he is the president of the United States. As of yet, though, he does not act that way, appearing promiscuously on television and granting interviews like the presidential candidate he no longer is. The election has been held, but the campaign goes on and on. The candidate has yet to become commander in chief.

Take last week's Group of 20 meeting in Pittsburgh. There, the candidate-in-full commandeered the television networks and the leaders of Britain and France to give the Iranians a dramatic warning. Yet another of their secret nuclear facilities had been revealed and Obama, as anyone could see, was determined to do something about it -- just don't ask what.

The entire episode had a faux Cuban missile crisis quality to it. Something menacing had been discovered -- not Soviet missiles a mere 100 miles or so off Florida but an Iranian nuclear installation about 100 miles from Tehran. As befitting the occasion, various publications supplied us with nearly minute-by-minute descriptions of the crisis atmosphere earlier in the week at the U.N. session -- the rushing from room to room, presidential aides conferring, undoubtedly aware that they were in the middle of a book they had yet to write. I scanned the accounts looking for familiar names. Where was McNamara? Where was Bundy? Where, in fact, was the crisis?

Richard Cohen is a Washington Post op-ed columnist. To continue reading his entire column, click here.