Jon Stewart has thumped with the folks over at Fox News before, both on "The Daily Show" and on occasion, to their faces. (Last week, Stewart went on "Fox News Sunday with Chris Wallace" and mockingly, but pointedly, went in on the conservative-leaning network.)

Now Bernie Goldberg, a frequent contributor to the network, has fired back at Stewart in a FoxNews.com blogpost titled "Is Jon Stewart Racist?" In it, Goldberg argues that liberals and conservatives are held to different standards when it comes to issues of race, and when criticizing black politicians in particular. Goldberg accused Jon Stewart of impersonating Herman Cain, the Republican presidential candidate, in an "exaggerated 'Amos & Andy' 'black voice.'"

"But why isn't Jon Stewart a bigot, when Limbaugh and Hannity and O'Reilly would be tagged as racists if they had done the very same thing?" Goldberg asks. "That's easy. Because Jon Stewart is a liberal and liberals aren't racists. Only conservatives are."

Here's video that has Goldberg so incensed. (The Cain bit starts at the 1:50 mark.)

The Daily Show - C#@k-Blocked Roundup - Tim Pawlenty & Herman Cain

Cain has said that Stewart doesn't like him because he's a black conservative, and that he's often mocked for his political leanings. "I have been called "Uncle Tom," "sell out," "Oreo," "shameless," he said at a recent campaign event. "So the fact that he wants to mock me because I happen to be a black conservative, in the words of my grandfather, "I does not care. I does not care."

Alex Alvarez has been watching this whole kerfuffle, and laments what he sees as the cynical way charges of racism are employed in American politics. "In the long term, it serves only to reduce matters of race and ethnicity to trump cards held, at the ready, in the back pockets of pundits and politicians on either side of the aisle, to be pulled out whenever it suits either side," he writes.

To spiral off Alvarez's point, Incidents like this --- hurling allegations of racism at an ideological opponent, and then the obligatory hand-wringing over whether that person or their behavior was in fact, racist --- reaffirm the idea that being called a racist is worse than actually experiencing racism. Goldberg isn't so much concerned with discrimination so much as he's mad that he feels that his fellow conservatives get a bad rap for perpetuating it.

This brouhaha also speaks to how Cain has made his blackness a major part of to his pitch to be president. (In 2008, Obama resorted to dogwhistling to black people, but his campaign assiduously avoided talking too explicitly or too long about race.) Cain is pitching himself as a familiar type --- the aggrieved conservative dogged by the media --- but with a racialized twist. Maybe it's because he needs to find some way to differentiate himself from a field of Republican candidates that's ideologically more or less the same. But part of it is because Republicans, like Goldberg, are clamoring for cover from charges of being the party of racists (see: the selection of Michael Steele as head of the Republican National Committee).

And who better to do that for them than an actual black man? Even if he's just a fringe candidate with no shot of winning anything?