Re John O’Sullivan’s “complete answer to his critics,” below, a smallish point and a larger point (and after this I’ll happily drop it):

The smallish point: In listing Truman, Nixon, Johnson, and Dubya right alongside Carter as failed chief executives, I simply applied the criteria that John himself had laid out. Now John has revised and extended his criteria, so to speak, such that only Carter failed in quite the way that, well, Carter failed. Every president is singular. Devising criteria that apply to one alone is easy enough.

The question, of course, is whether doing so is useful. And in this case–here the larger point–I doubt it. What was the assertion by John Derbyshire that started the exchange? That whereas a successful Obama administration might indeed improve race relations (as John O’Sullivan had suggested), the failure of an Obama presidency might instead make race relations quite a lot worse. That strikes me as an entirely valid concern–and worth bearing in mind whether Obama were to fail on the scale of Jimmy Carter or merely (as John O’Sullivan would have it) to prove as catastrophic as, say, Richard Nixon.