That’s Jon Favreau’s view of the Tea Party:

Over the last few weeks, it has demonstrated again that its intent is not to shake up the establishment but to burn down the village. As a Democrat, I disagree with its policy positions, but its policy positions alone are not what make the Tea Party so dangerous. What makes the Tea Party dangerous is its members’ willful disregard for the most basic tenets of American democracy. They do not believe in the legitimacy of our president. They do not believe in the legitimacy of decisions handed down by our Supreme Court. Unlike President Obama, Harry Reid, Mitch McConnell, John Boehner, or a host of other Democratic and Republican lawmakers who grasp the basic reality of politics, they have never, not once shown a willingness to compromise on anything. Merely uttering the word is enough to draw a primary challenge.

Jonathan Bernstein adds that once “resistance to compromise itself becomes an important principle, episodes such as the shutdown are hard to prevent”:

The key point to emphasize here is that the problem with the Republican Party, or at least the problem that causes shutdowns and other such disasters, isn’t that they’re “too conservative.” If that was all that was going on, they could still reach compromises with Democrats. The problem isn’t about ideology, at least not as we conventionally think of it; it’s about willingness to compromise and to work within the political system.

Finally, Jeff Shesol dismisses the idea that there is some kind of civil war happening inside the GOP:

The extremism of our own age—Tea Party extremism—“contaminates the whole Republican brand,” as David Frum has written. And he’s right. But Tea Party extremism is not, as this implies, a betrayal of the party’s belief system. It is, instead, a crystallization, a highly potent concentrate, of the party’s belief system. The free-market dogmatism, the tax-cut catechism, the abhorrence of nuance and science and government and fact—these did not bubble up during town-hall meetings in 2010 but flow from the same deep well from which establishment Republicans like Mitch McConnell (Goldwaterites, all) have long been drinking. Frum and other sensible conservatives yearn for a Tea Party exit—maybe even an expulsion—from the G.O.P. But it cannot be expelled, because in this case the parasite is a creation—in some ways a perfection—of the host organism itself.