Former President Bill Clinton bows as President Barack Obama walks on stage after Clinton’s address to the Democratic National Convention in Charlotte, N.C., on Wednesday, Sept. 5, 2012. (AP Photo/J. Scott Applewhite)

Why did Bill Clinton bow so deeply before Barack Obama after his amazing barn-burner of a speech Wednesday night?

I mean, his bow wasn’t a bob of the head; it wasn’t a slight slump of the shoulders or a passing nod. It was practically a salaam. He bent double at the waist, taking the kind of bow a courtier might make before a king. Did Clinton—right after defending Obama’s policies better than Obama ever has—feel he still had to overcome any lingering doubts about his loyalty?

Probably. But I think in that moment Clinton was also schooling Obama in humility.

The reason politicians find themselves transfixed by Clinton—whether they’re old opponents like George H.W. Bush or longtime allies like Rahm Emmanuel—has to do with the way he understands power as a source of personal struggle. Clinton subscribes to the ancient belief that every leader must give up something, usually something he or she loves, for power—as Odin gave his eye and MacBeth his honor. There’s a great scene in the HBO movie A Special Relationship in which Clinton takes the measure of Tony Blair’s character by asking him what he’d be willing to do to stay close to power under incoming President George Bush. That, as it turned out, was the right question to ask about Blair.

Clinton himself gave up critical parts of the New Deal—signing the repeal of the Glass-Steagall Act, compromising on welfare reform—to steal victory out of the jaws of defeat when Newt Gingrich took the House in 1994. Clinton can give you chapter and verse on why he gave in and what he got in return for those deals, but there’s little doubt they contributed significantly to the mess we’re in.

But he’d go on to tell you that is what a successful politician has to do: you must have power in order to use it at some critical point you can’t really anticipate, and a great politician’s legacy is all about crucial decisions made under the pressures of the moment. Had 9/11 happened one year earlier, you’d have seen just how important it can be to have someone like Bill Clinton in power.

Unfortunately, it happened when it did. Clinton never faced a truly epochal crisis. He did have to give up his pride over the sex scandals the GOP used to impeach him, and in our celebrified culture, that was no easy thing. But it wasn’t 9/11; it wasn’t even the collapse of the world economy.

Barack Obama, on the other hand, has had to give up very little, at least nothing that caused him visible agony, to get where he is—after all, he won the Nobel Peace Prize just for getting elected. A leader forges a bond with his people by seeming to humble himself before them and yet still carry on. Obama needs to grasp the nettle of his humiliation at the hands of the Republican House last year and make it part of his, and our, story of economic and political redemption.

This isn’t about studying hard and coming up with the right answers, or figuring out where the halfway mark is between two opposing philosophies. Obama can’t win this by overachieving (an Obama trait Jodi Kantor described so well). And beating the hideously unpopular Mitt Romney by one or two points won’t do it. He needs other people to win with him. He needs a Senate and a House he can work with, and as a sitting president he needs to do all he can to shape them in his image—we’re all going to hold him responsible for what Congress does anyway, so he’d better bring his party along.

Look at me, Clinton said with his bow, I’m giving up control; would it be so hard for The One to show a little vulnerability out there, maybe admit he’d made a mistake or two? Michelle worked so hard in her speech to underline how much like us her husband has always been, balancing student debts, living with dumpster furniture and driving a car with a hole in the floor; maybe he can give up the suave cool for once and let the world see that now he needs us.

After the bow Clinton and Obama hugged and waved together to the crowd, and then walked backstage as the television cameras followed them. Just as they were about to leave the stage, Clinton saw someone he knew, he smiled, and, well, watch (starting at about :43):

That’s pressing the flesh, and Clinton was virtually grabbing Obama by the scruff of his neck and forcing him to do it, too. Clinton can teach by example, but Obama was still the first one to turn heel and walk away.