I've always been simultaneously amused and bemused by the Jon Stewart approach. At its best, as in this clip, he works by simply letting truths speak for themselves. Sometimes he has to fudge things a bit to make his points, but in this clip, all he really do is sit back and play a stream of clips. The points make themselves.
We on the left find this very funny. And I think we also have an inner monologue that goes something like this: "This stuff is so obvious; how could anyone possibly not see what is wrong with the Republican party?!!" I know I have thought things like that. Even when you know you're being condescending, it's hard not to think that the other side are complete idiots. It's frustrating, of course, and you get shows like Stewart's that seem to think that if only the truth could be revealed to the masses, they would immediately agree with us.
Of course, that's not actually the case. As J.L. Austin famously pointed out, there are some statements that are demonstrably true or false. "The sofa is on fire" is either true or false. But then there are statements that are not measured in terms of falsity, but rather in their performative effect. By this, Austin means that statements can actually cause things to happen, and are measured by this. His most clear example is a minister performing a wedding. When the minister says, "I now pronounce you husband and wife," that statement is neither true nor false. Rather, because of legislation giving the minister certain authorities, the two people are bound by those words into a legal contract. We measure the statement "I now pronounce you husband and wife" not by its truth, but by whether or not it works. If, for example, it occurred without the proper authorization ("I do") of the couple, the minister's statement would not have the desired effect.
Anyways. That's the brief (really brief) version of what we academic types call "performativity." This is exactly the world of political discourse, which is measured not in truth versus false, but in its effect. The (sad? maybe.) fact is that you can go around pointing out errors of logic in Republican positions all you want, but doing serves more as a cheerleading function for the committed. Which is fine, but ideally our goal should be change, not a sense of superiority. It's why in some ways Stephen Colbert's approach is possibly the more effective: by pretending to be a right-wing blowhard, I think he actually is much more effective at subverting Republican talking points than Stewart. We live in postmodernity, and it's best to use tools appropriate to the times.
It also means he avoids some common traps. Jon Stewart and others on the left have this bad habit of often descending into very unpleasant political rhetoric when they think they can seize a chance to introduce more truth into the world. Earlier in the show from which the above excerpt comes, Stewart had another bit in which he tore into the hypocrisy of Republicans, and had a little skit in which the Stewart news team camped out in the men's room at the Republican. Pointing out hypocrisy is always a good time, and it could have been a funny skit, but it quickly became apparent that the reason we were supposed to laugh at the Republicans was not because they were hypocritical, but because they liked gay sex at all. "Gross," they seem to say, "men who like men!"
There is a lot of that on the left. Back when the Larry Craig and Mark Foley scandals were in full swing, there was a lot of homophobic discourse on the left. Just like during the primary there was a ton of sexist discourse on Daily Kos and a lot of racist stuff on MyDD. And you know what? There has been a lot of sexist attacks on Palin. Just because Republicans are crying foul for once doesn't mean it's not true. So you know what, my comrades? Cut it out. The problem with Palin is not that she is a mother, or a woman, or that she is "inexperienced," whatever that code word might mean to you. The only problem with Palin is that her beliefs in things like abortion, the environment, education, gay rights, national defense, and just about every thing, would take this country down the wrong track. I think that's enough.