Matt Yglesias pushes back against claims, by Ross Douthat among others, that the Democratic Party is a fragile coalition held together only by Hillary Clinton’s personal popularity. He’s right; I’d just like to add a few thoughts.

As Yglesias says, Democrats are remarkably unified on policy. They want to preserve health reform; they want to preserve financial reform, even though some would want to push it further; they want action on climate change; they may be conflicted on immigration, but that’s mostly internal soul-searching rather than a division between party factions.

This policy unity has been helped by the fact that Obama has had a moderate degree of success in achieving these goals. If he had had an easy time, the party might be divided between those wanting more radical action and those not in a hurry; if he had failed utterly, the party might be divided (as it was for much of the past three decades) between a liberal faction and a Republican-lite faction. As it is, however, Obama has managed to achieve a lot of what Democrats have sought for generations, but only with great difficulty against scorched-earth opposition. This means that the conflict between “the Democratic wing of the Democratic Party” — exemplified these days by Elizabeth Warren — and the more pro-big-business wing is relatively muted: the liberal wing knows that Obama has gotten most of what could be gotten, and the actual policies haven’t been the kind that would scare off the less liberal wing.

The Wall Street tantrum of recent years also, in a peculiar way, helps party unity. Bankers who used to support Democrats have thrown their support to Republicans, whining all the way that Obama is looking at them funny; this has reduced their influence on the Democrats, leaving a workable consensus about regulation and tax policy among those left.

How do personalities matter in all this? Not so much. In the end, Obama implemented Clinton’s health plan (remember how he was against mandates?), and Clinton, if elected, will continue Obama’s legacy. The party is willing to rally around an individual because it’s unified on policy, not the other way around.

In fact, it’s the Republicans who desperately need a hero. In retrospect, they needed W much more than they realized: he combined policy fealty to the plutocrats with a personal manner that appealed to the base, in a way no Republican now manages.

Stuff happens; a recession in 2016 could sweep a Republican, any Republican, into the White House. But the Democratic coalition isn’t fragile, while the Republican coalition is.