Jon Stewart's announcement last Thursday of his "Rally to Restore Sanity" on Oct. 30 has, not surprisingly, generated significant interest from"Daily Show" fans. (The current number of people signed up on the rally's Facebook page is 140,000). But it also prompted some confusion, even from longtime fans. What is Stewart trying to achieve? Does this mark a more formal embrace of politics? Will this change the way he's perceived?

Salon spoke to Taylor Branch, Pulitzer Prize-winning civil rights historian and scholar of mass political movements, about Stewart's role in popular culture and politics and what benefits and risks the rally holds for him. (We also asked Branch about the controversial New York Times Op-Ed he recently penned expressing sympathy for Glenn Beck's 8/28"Restoring Honor" rally.)

What do you think the goal of Stewart's rally is?

Well, I don't know. He always says his job is straightforwardly to entertain and poke fun at the news.

Do you think that's true?

Do I believe him? I don't know. He has stepped out of that role a couple of times. Years and years ago he went on"Crossfire," on CNN, and scolded them, saying that they were just entertaining people with emotional argument for argument's sake, without any interest whatsoever in asking any questions or solving any problems. And that therefore it was just entertainment -- and that that was his job. That seemed to be a foray into serious politics, you know, saying,"I'm supposed to be the clown, not you guys." I don't know whether that's what he has in mind here or not, because he hasn't really said. But I think whenever people in a public position like that do things that are unexpected, that involve some sort of surprise and or risk, we need to pay attention to what they say, because maybe it'll provoke something new.