In the 1960 Kennedy-Nixon debate it was widely reported that Mr. Nixon was in ill health. The result was a pale, sweating Nixon against a vibrant, tanned John F. Kennedy. Of course, Bobby Kennedy bird-dogging the thermostat didn’t help Nixon’s predicament. As they say, the rest is history (with a lot of help from alleged vote-stuffing in West Virginia, that is).

Well, Burns & Haberman have a very interesting report via Texas Monthly’s Paul Burka, who’s been watching Perry for decades. It goes like this…

Perry was clearly off his game during the tea party debate. He looked uncomfortable, his face was strained, his combativeness was muted. He looked to me like a man with back pain. I wondered if he were wearing a brace. I’ve had back surgery, and it hurt to watch him.

I thought Romney won the debate. He took it to Perry from the outset, and he went for the intimidation play, staring his rival in the face as Perry gave his answers. Perry stumbled several times. I think of him as someone who has a great feel for his constituency, but I don’t know how anyone could have had a feeling for that constituency. That was one scary audience. Perry muffed the border fence question, muffed the dream act question (though his answers were sincere and courageous, and I agree with him in both cases). I thought he muffed Bachmann’s attack on the HPV question too, saying that he raised $30 million and he couldn’t be bought for $5,000. Croney capitalism is going to stick to Perry. There are too many instances””Harold Simmons and the nuclear waste dump, Bob Perry and the Residential Construction Commission, recipients of emerging technology grants, fund managers who got to invest teacher retirement money. It is a rich lode, and it is going to be mined by his enemies.

He just wasn’t presidential. He was low-energy and the feistiness wasn’t there. That’s why I’m wondering whether the back operation didn’t go well, or whether he got irked because Bachmann got to his right on the HPV issue. Another explanation could be that Perry has been around so long and has been so successful in politics that our expectations are high, and they are hard to meet. He just didn’t seem presidential, and I think the reason was that he was hurting.

[…] The big question mark for me is Perry’s health. Tonight was one of those rare moments when the camera didn’t love him. He has plenty of time to get back on his game, assuming that his physical condition holds up. But I am beginning to wonder whether he will have the stamina to hold up to the demands of a grueling campaign if his back is injured. For now, that’s just as big a threat as Romney is.

National politics is a cruel sport. You’ve got to be 111% on your game, especially against an iron man candidate like Mitt Romney, whose entire strategy is built around out lasting the flavors of the month.

The other problem for Perry is that at the national level you’ve got to be able to talk policy, which he has proved he can’t do past vacuous quips.