A reader writes:

"Because he is" is way too simple.  He is a self-described "Rockefeller Republican", from New Hampshire, no less.  So would he call himself a Republican today?  And the real question is, would Rush Limbaugh and the rest of the right-wing welcome him as a Republican if they look past his military service? Of note, I came across another person who had called himself a "Rockefeller Republican" - Jackie Robinson.  Guess what, he campaigned for Hubert Humphrey in 1968.

Another reader:

It would be as if Tommy Franks quit in 2004 and ran against Bush. He has no economic/domestic credentials at all (and if Obama in vulnerable in 2012, it will be on the economy, not foreign policy), and every criticism has an automatic retort: why didn't you work to fix this when you were inside the tent? If some of the fringes of the GOP are pining for Petraeus, I take more of a sign that those fringes really believe that the usual suspects of potential GOP nominees just cannot win against Obama and they're grasping at anything they can to find new blood.

Jason Zengerle follows up on his previous post and compares Petraeus to Wesley Clark:

Clark might have been famous with the sort of folks who find their heroes in Richard Holbrooke books, but he didn't have that much of a national profile, which no doubt contributed to his problems. And, of course, part of the big appeal of Petraeus at the moment is that he seems to be very much above politics. He'd have to sully himself just by entering the presidential race, and then once he was out on the stump, doing the things candidates have to do, I think a lot of his shine would come off.

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