A black Republican who has rankled liberals and suddenly risen in prominence is torpedoed with old allegations of sexual harassment as he challenges the conventional wisdom about how African-Americans think and pursues an important position atop the federal government.

Haven't we seen this movie? Get ready for the sequel.

Politico reported recently that two women -- whose names are being withheld by the website -- accused Herman Cain of sexual harassment in the 1990s while the businessman led the National Restaurant Association, and that a financial settlement "in the five-figure range" was reached to keep the story quiet.

When confronted with the allegation, the GOP front-runner showed that he is new to politics by mangling his responses in one media interview after another.

At first, Cain went with the tried and tested approach: "No comment." Then he claimed to know nothing about the case. Then he claimed that he did know a little about the case, but that he didn't know there had been a settlement. Then he tried to tell us that there was a difference between a "settlement" and an "agreement." And, by the end of the day, he was admitting that there had been a settlement and that, in the case of one woman, it had amounted to about three months salary.

It was both amusing and painful to watch. I'm not sure whether to applaud Cain for not knowing how to lie with the panache of other Republican presidential hopefuls, or tell him to run for the exit. I hope he doesn't quit the race, as some Beltway commentators are suggesting he should do -- not because this scandal is so bad that he can't recover, but because the elite media can't wait to clear the field and get to what they think will be the main event: Mitt Romney versus Barack Obama.

There is no question that Cain's handling of this story was atrocious. But what is also troubling is that this scandal has a familiar ring -- one that goes back 20 years to the confirmation hearings for then-Supreme Court nominee Clarence Thomas.

I don't know about you, but I'm getting awfully tired of sexual harassment being the preferred line of attack against black conservatives. This isn't to say that sexual harassment is acceptable -- whether it's a proposition or the creation of a hostile work environment.

But the whole thing makes me queasy in light of the ugly history in this country of black men being described in sexually charged terms. I don't care who the attack is leveled against; anyone who plays with the idea of a black man acting inappropriately toward women is playing with dynamite. Liberals who rejoice in the Cain story should remember that.

Herman Cain and the decline of black conservatism

And why are black conservatives singled out for these kinds of attacks?

Consider how many of them hold high office in this country. Not many. If you counted up all those who serve in the House, the Senate, and the 50 governorships, you'd still have less than a handful. Since the 1960 presidential election, African-Americans have shunned the GOP and tended to vote Democratic. Politicians who break from that tradition automatically become a target, and their critics will pummel them with anything they've got.

After all, it's not like African-American men are the only ones ever accused of sexual harassment. The alleged perpetrators come in all colors.

During the 1990s, even before the Monica Lewinsky scandal, President Bill Clinton could have easily become the poster boy for sexual harassment because of allegations by a former hotel worker named Paula Jones. While Clinton was impeached by the House of Representatives, he long ago closed that chapter in his life, and now he's considered one of the Democratic Party's elder statesman.

There was also the notorious Tailhook scandal, where more than 100 aviation officers from the U.S. Navy and U.S. Marine Corps -- most of them white -- were alleged to have sexually assaulted and/or sexually harassed more than 80 women at a gathering in Las Vegas. All this happened just one month before the Thomas hearings, and yet we're likely to remember one of these events much longer than we do the other.

Somehow, it was Thomas whose name became synonymous with allegations of sexual harassment, after Anita Hill came forward in October 1991 and claimed that while he was her boss at the Equal Employment Opportunity Commission, he made sexual advances and created a hostile work environment.

Many Americans look back at Thomas' confirmation hearings and think they were mainly about accusations that Thomas directed sexually blunt language at Hill. But for me, what they were really about wasn't dirty talk as much as dirty politics. Black conservatives ask us to think outside the box, and so -- as some people see it -- they're asking for trouble.

The hearings were also about freedom -- the freedom to indulge in independent thought, even if it means biting the hands of liberal benefactors. You heard that criticism leveled at Thomas, who opposes affirmative action even though -- according to his critics -- he benefited from it. And the public humiliation that Thomas suffered remains a prime example of the liberal establishment trying to put someone in his place.

Now, in an outrageous example of patronizing language that borders on hate speech, MSNBC analyst Karen Finney declared that the only reason that Cain is popular with white Republicans is because "he's a black man that knows his place."

We could have guessed this was coming, sooner or later. In the latest installment of "Liberals Gone Wild," the black Republican presidential candidate who knows his place is put in his place by a liberal commentator.

Cain should be glad about one thing. As the attacks on him intensify, it proves definitively that he's moving up in the world. As voters continue to respond favorably to the fact that he's not a professional politician, he's gone from novelty act to legitimate presidential contender.

When that happens, there are those in both parties who will try to destroy you. Even if it means -- just as it did 20 years ago -- hurting the country in the process.

Editor's note: Ruben Navarrette Jr. is a CNN.com contributor and a nationally syndicated columnist. The opinions expressed in this commentary are solely those of Ruben Navarrette Jr.

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