For more on Mr. Lehrer, read this great interview. Here's a taste:
O: Do you feel that you had any impact?
TL: That's hard for me to say. I don't think this kind of thing has an impact on the unconverted, frankly. It's not even preaching to the converted; it's titillating the converted. I think the people who say we need satire often mean, "We need satire of them, not of us." I'm fond of quoting Peter Cook, who talked about the satirical Berlin cabarets of the '30s, which did so much to stop the rise of Hitler and prevent the Second World War. You think, "Oh, wow! This is great! We need a song like this, and that will really convert people. Then they'll say, 'Oh, I thought war was good, but now I realize war is bad.'" No, it's not going to change much.
O: Is comedy important?
TL: Comedy is very important, yes. For one thing, it keeps you sane. But it's not really a conversion. I mean, it's marginally a conversion, because if people tune in or go to a nightclub or even watch television, and hear that a lot of other people are laughing at something you thought was not funny, at least it'll force you to reconsider. I know people who've heard "The Vatican Rag" and then converted, so to speak. They'd think, "Hey, wait. There are actually people who take that as funny. I'm not the only one." I've always done some good along those lines. Many people over the years have said, "Oh, 'The Vatican Rag' changed my life." It's not that they were convinced of something they weren't convinced of before; it's just that now they realize it's okay to laugh. They're not the only ones.