I don't take a gun into the park, and I wasn't suggesting that anyone else should. As I said, I carry a gun when I am concerned about people, and I am less worried about running into the wrong kind of people in a national park than in a national forest or some other place that has less visitors and is less frequented by any sort of law enforcement.
Getting back to bears: I'm 5'11'', weigh 215 lbs, and I am in fairly good shape. I don't think I'm a tough guy or anything, but there is no wild animal in the Smokeys that wants to tangle with me. I'm not so naive as to think I could outfight a bear: I know any adult bears could wear me out easily if it decided to. But the trick is, it doesn't know that. What it does know is that I'm big enough to be a problem and that it might very well might get hurt in the process of taking me down, which is lethal in their world. So they choose to go the other way.
Life is hard. But it's a lot harder if you're stupid.