Sarah Palin is a quitter.

I'm not much of an Andrew Sullivan fan, but I agree with what he writes about it:

In the end, I think, the one thing to say is that the Republican party is in such a total state of collapse and incoherence that it actually believed she could be a future president; and that John McCain was so reckless, so cynical and so cavalier that he was prepared to rest the national security of this country on her shoulders if he, in his seventies, were to become unable to fulfill his duties or die. In some ways, this is a moment to reflect on McCain, and his irresponsibility, not Palin and her drama.