Andrew Sullivan argues that Kerry mentioning Dick Cheney's lesbian daughter is not some underhanded smear.
You have to regard homosexuality as immoral or wrong or shameful to even get to the beginning of the case against Kerry.
Not necessarily. What you do have to recognize is that we don't live in a perfect world and that, unfortunately, some voters will make a negative association with Cheney as a result of Kerry's remark. Here's an example. If in the debate Bush had referenced Kerry's Catholicism, big deal. Anti-Catholic prejudice is pretty much dead. On the other hand, if Richard Nixon had referenced Kennedy's Catholicism (something that, much to his credit, he never did) in the 1960 debates, it would have been a big deal since a significant number of voters in that election did have anti-Catholic prejudices and such a reference would have triggered or reinforced their bias against Kennedy. It didn't matter what Nixon thought about Kennedy's Catholicism. What mattered is whether he perceived an anti-Catholic bias in the public and whether he played to that bias.
The same goes for race issues. If I wanted to do in Clarence Thomas among racist whites, I could run around talking about how much I respected his interracial marriage. Hell, I could even run puffy TV ads showing Thomas and his wife, calling them "my esteemed opponent and his lovely and charming wife." Even if I thought interracial marriage was fine, I'm still playing the race card. And in some ways, that's far more reprehensible and cynical than if I were honestly racist.
That said, Sullivan is absolutely right when calls out conservatives for being "shocked, shocked" at the idea of using gays as a wedge issue.