You can't turn anywhere these days without seeing Borat's mug grinning back at you. Much ink has been spilled about how offensive the film is, but I think this quotation from a blog I read this week says something interesting about why we love the film.
The film is subversive in that its most likeable characters are the blacks, the Jews, and the gays. And that the ones who make us cringe in shame are those who have been historically at the top of the American culture.
Some have called Cohen's characters mean spirited, but Cohen does not make fun of them. All Cohen does is ask questions that allow those being interviewed to make themselves look stupid. The people on the show who came across as having integrity were those who were willing to say "I can't go on with this." The ones that stick out as having the balls to do that were Andy Rooney, Marlin Fitzwater and Donald Trump.
But the frat guys promoting slavery and the cowboy suggesting we should kill all the homosexuals deserve to be made to look like idiots. That is Cohen's appeal.