Michael Gerson’s column today imagines (as a thought experiment) Barack Obama’s first 100 days in office as a sort of black comedy of foreign policy errors. After Obama’s imagined meeting with Iranian President Ahmadinejad, Gerson licks his chops over the following scenario:

The New York Post runs a front-page picture of the Obama-Ahmadinejad handshake under the headline “Surrender Summit!” The story notes another of Obama’s historic firsts: the first American president to meet with a Holocaust denier. The Israeli prime minister publicly asks, “Why is the American president meeting with a leader who calls us ‘filthy bacteria’ and threatens to wipe us ‘off the map?'” Tens of thousands protest in Tel Aviv, carrying signs reading “Chamberlain Lives!”

Of course, this and several other imagined gaffes will never take place, Gerson opines, because “Sitting behind the Resolute desk is a sobering experience that makes foolish campaign promises seem suddenly less binding.” The observation leaves Gerson in a position to reflect that “it is a bad sign for a candidate when the best we can hope is for him to violate his commitments.” This is the same Michael Gerson who only a few weeks ago extolled the Obama movement as “the return of idealism” and said further that “The day an African American stands on the steps of the U.S. Capitol — built with the labor of slaves — and takes the oath of office will be a moment of blinding, hopeful brightness.”

All hopefulness aside, it was inevitable that the shine would wear off Obama’s fame long before any inauguration — inevitable that the rough and tumble of negative campaigning would humanize and humble him. But I, for one, remain hopeful that this young man will rise to the occasion as he has each time in past months when some adversity has slowed his progress, and continue to persuade us that the United States of America can still become the country Martin Luther King and Robert Kennedy dreamed of.

Clinton’s victories in Texas and Ohio have allowed her to renew her claim to entitlement. She can now pursue this claim through the August convention, perhaps, and even claim the nomination by persuading a sufficient majority of superdelegates to join her, especially if she wins Pennsylvania and continues to add to her pledged delegate total.

Thus, Obama can lose even if he wins, and that prospect sharpens the difference between his campaign and Clinton’s. Obama really is campaigning for national unity, or failing that for a sufficient majority to claim a mandate for change in the way Washington does business.

I hope he will continue to do so.