Back when I first began reporting about policy, I got a piece of advice I've tried never to forget. I haven't done a particularly great job of it, because I've forgotten who actually gave it to me. But I've remembered the actual line. "The world isn't here to please you," I was told.

If you're around policy research enough you'll end up reading a lot of studies that violate your intuitions, your theories, your hopes, and even your values. You'll have the instinct to brush them away or come up with some reason they're wrong. In those moments, I was told, it's worth remembering that the world isn't here to please you.

Politics isn't here to please you either. And this, I think, is the core of the debate over whether "presidential leadership," whatever that actually means, can fix Washington.

In general, the difficulty of engaging with "the president should lead" theory of American politics is, as Jonathan Chait writes, "it’s not quite coherent enough to rise to the level of wrong." Or, more to the point, it's not quite specific enough to rise to the level of answerable.

In these arguments, "presidential leadership" plays the role of the briefcase in "Pulp Fiction." It drives the entire story, yet we never get to see what's in it. Peggy Noonan says of today's dysfunctional politics, "if you're a leader you can lead right past it." How? Well, uh, look over there!

Maureen Dowd writes that the job of the president "is to somehow get this dunderheaded Congress, which is mind-bendingly awful, to do the stuff he wants them to do. It’s called leadership." Actually, I think getting people who disagree with you to do what you want them to do is called "the Jedi mind trick," but I digress.

It's impossible to argue with these columns because they never actually say what they're about. If Noonan or Dowd explained what the president should actually do, we could have a discussion. But they don't, presumably because they can't.

The National Journal's Ron Fournier has also been a big proponent of "the president should lead" theory of American politics, but, to his credit, he has spent a lot of time generously engaging with his critics on the issue. So unlike with a Dowd or a Noonan, it's possible to map the boundaries of his argument.

When asked what kind of presidential leadership could bridge the divisions in American politics, Fournier demurs: That's why he's glad he isn't president, he says. But he's certain that Obama can answer the question, or at least should have to answer the question. His oft-expressed view is that dismissing the power of presidential leadership to fix American politics is simply "giving Obama cover to fail." It's "raising the white flag."

This is a more interesting argument: Fournier is saying that whether presidential leadership can or can't fix the situation is almost immaterial. If the public stops believing presidential leadership can fix the situation, then the situation will get worse, as the president will have less incentive to try and fix it.

Fournier and other adherents of the Green Lantern Theory of the Presidency are caught between a question they can't answer and an answer they can't abide. They don't know exactly what Obama — or any other president — could do to overcome the structural polarization that's cracking Congress. But the idea that there's nothing the president can really do is too displeasing to entertain. It suggests that politics is broken, and it won't be fixed, at least not anytime soon. And that's an unacceptable answer, even if rejecting it leaves you with an unanswerable question.

They have it backward. It's raising the white flag to cling to an unanswerable question rather than staring down an unpleasant answer. The problems of American politics today are not overly complicated, or even overly controversial. They're just hard to fix.

The two political parties have polarized. Unlike in the 1960s, when Jesse Helms was a Democrat, and George Romney was a Republican, today's Republicans agree with Republicans, and today's Democrats agree with Democrats. That, plus the zero-sum nature of elections and the rise of an ideological media and interest-group infrastructure that credibly threatens dissenters with primary challenges, has made bipartisan consensus on most big issues structurally impossible.

That's fine. It's how most political systems operate, in fact. But our political system, which is centered around Congress rather than the White House, requires extraordinary levels of consensus to operate smoothly. That leaves us with two choices: Either figure out a way to depolarize the parties or change the rules of the political system so it can operate more smoothly even amid polarization.

We're not going to figure out a way to depolarize the parties. Whenever you think of the irenic Washington of the '50s and '60s, think about Strom Thurmond, one of the most ideologically conservative members of Congress, serving as a Democrat. The de-polarized parties of the mid-20th century were a historic aberration that had more to do with race scrambling our politics than anything else. They're not coming back, nor should they. The most conservative members of Congress shouldn't be in the Democratic Party, nor should liberals be in the Republican Party. Voters deserve a choice between two distinct political coalitions.

But that means the work of repairing American politics is the work of understanding what tweaks and reforms are needed for the American political system to withstand this new world of polarized political parties. That's going to be a lengthy and difficult project, and many political fights in the coming decades will, on some level or another, be about it.

But that work is made harder by pundits who continue to falsely promise that the glowing briefcase of president leadership can fix what ails us. Telling the American people that the only thing missing is the president being more awesome promises them the easy way out. It says that all they need to do to fix our politics is get inspired by a new presidential candidate and then cast a hopeful vote for him or her at the polls. That's terrifically convenient, because that also happens to be the part of American politics that voters most enjoy participating in and that media most enjoys covering. (It's also convenient for the media, as Greg Sargent writes, because it keeps them from having to take sides in ongoing policy debates, but that's a slightly different issue.)

But since the problem in American politics is not presidential leadership, telling them that the president — whether this one or a new one — can fix it traps voters in an endless cycle of inspiration and disillusionment. They vote for presidents expecting them to be "uniters," expecting them to "change Washington," and then they're bitterly disappointed when their heroes fail. But on this score, presidents are going to continue to fail because they can't possibly succeed.

It's not waving the white flag to say that the president can't fix Washington. It's waving the white flag to resist other explanations because they're too depressing, or because the work they imply is too hard, or the fight they require will take too long. If the first step toward political recovery is admitting we have a problem, surely the second step is admitting what the problem actually is.