With admirable calm, President Obama has sought to deflect the supercharged politics of race by expressing his optimism about American attitudes and ignoring the most extreme statements by his critics. For his own sake, as well as the nation’s, he is wise to give a pass to the likes of Glenn Beck and Rush Limbaugh. That is not, however, what they deserve.

The behavior of those media provocateurs over the past few months is almost beyond parody. They call the president a racist, even though there is no evidence of prejudice on his part and much evidence to the contrary. They demand that nobody should ever point out racial prejudice, but spend hours on the airwaves making false claims of bias against whites. And they whine constantly about being called racists, even though the president has never made that accusation against them.

“You can’t get your agenda,” protested Beck the other day, speaking of the president, “so you unleash the hounds and point the fingers, and everybody is a racist.” That was around the same time Obama’s spokesman said quite emphatically that the president does not believe his opponents are motivated by racism.

But since Beck and Limbaugh seem to be obsessed with this touchy subject, let’s examine their record. It turns out that both established their keen racial sensitivity on air long ago.

Back when Beck was simply a coked-out zoo-style morning talk jock on a Kentucky station — rather than a national political philosopher — he regularly mimicked African-American speech patterns for fun. “He used to do a funny ‘black guy’ character, really over the top,” recalls one of his former colleagues, quoted by biographer Alexander Zaitchik in a fascinating Salon profile.

Beck also became a devotee of the Mormon crank author and conspiracy theorist W. Cleon Skousen, whose writings he enthusiastically promotes to this day. Among Skousen’s pet theories was that Southern slave owners were actually the victims of the plantation system, which according to him favored the lazy and pampered slaves, whose children he called “pickaninnies.” Like his ultraright friends in the John Birch Society and kindred groups, Skousen was a dedicated foe of civil rights legislation.

Does that mean Beck is a bigot? If Obama had ever endorsed the writings of Louis Farrakhan, replete with vile slurs against whites and especially Jews, that would certainly be enough for Beck — who says he believes that the president has “a deep-seated hatred for white people, or the white culture.” That must be why the Obama White House has so many whites of all ethnic and religious backgrounds advising the president, from the Cabinet down.

As for Limbaugh, perhaps nobody remembers the time that he told a black caller to “take that bone out of your nose”; or the time when he said the nonviolent NAACP “should get a liquor store and practice robberies”; or the many times when he would play the “Movin’ On Up” theme from the old “Jeffersons” TV show to accompany his commentary about Carol Moseley Braun, the first black woman in the United States Senate. He used to do mocking bits in black dialect, too. But who needs to remember those sorry episodes when he continues that ugly pattern on air nearly every day?

The Limbaugh show reached a new low recently when he began a campaign around a school-bus incident in Belleville, Ill., in which two black students were videotaped beating up a white kid. Police authorities first said they believed the assailants were motivated by race, but later said it was just a nasty bullying assault (for which the two little thugs are now being prosecuted).

But Limbaugh could not resist the opportunity to turn that nastiness into something much more dangerous. “It’s Obama’s America, is it not? Obama’s America — white kids getting beat up on school buses now. I mean, you put your kids on a school bus, you expect safety, but in Obama’s America, the white kids now get beat up, with the black kids cheering.” In a more reflective mood, he later asked, “Can this nation really have an African-American president?”

Yes, we can — and despite the racial poison spread by Beck and Limbaugh, most Americans are proud that at long last, we do.

Joe Conason writes for The New York Observer.