Herman Cain was in the center of a firestorm, largely of his own making, yesterday. He knew before he entered the presidential race that he had a sexual harassment settlement in his past. He knew, ever since Politico started questioning his campaign, that a story was afoot. He knew he had to get the story out quickly and truthfully. And yet, by the end of the day, the business executive peddling his leadership skills and know-how looked somewhat like the hapless PBS executive who eventually got ousted for screwing up the Juan Williams firing.

Cain’s response to the scandal failed in at least four significant ways. First, his story changed multiple times, giving the impression of untruthfulness. Second, he didn’t make sure everyone on his campaign was on the same page. Third, he made wild accusations of a witch hunt without denying the substance of the original story (e.g., his employer settled at least one sexual harassment claim brought against him). Fourth, he dominated the news for an entire day without resolving key questions.

We’ll no doubt hear more about the allegations and defenses in the days to come. There will be a spate of “Is he finished?” and “Is Cain telling the truth?” stories. He will be asked about the allegations in every interview and appearance for some time. His credibility, organization, competence and judgment will be the subject of endless debate.

Those who believe him (especially the Cain-iacs who have come to resemble the Palin World fanatics) will accuse critics and reporters of racism. His fans will try to make a martyr of him, casting the MSM in the role of the villain.

In other words, it will become a full-time drama in which, at best, Cain may be thought to be an incompetent crisis manager and, at worst, a creep and a liar. Suddenly his selling points — “problem solver” and ”truth-teller” — risk becoming laugh lines. He may survive, choosing to stick in there and battle through what will be the worst weeks of his campaign, but it’s going to hurt him with those who don’t like the fuss, don’t believe him or don’t think he handled the scandal responsibly.

Yesterday morning I asked the Cain campaign a series of questions: Was Cain ever questioned about National Restaurant Association attorneys about the allegations? Was a lawsuit or administrative claim ever filed? Did Cain sign a settlement agreement? Did he ever file a claim for indemnification with NRA or an insurance carrier? Was he ever deposed?

After 8 p.m. his spokesman J.D. Gordon responded that Cain had answered all of these, except for the indemnification issue, during the course of the day. That’s not true. (For example, Cain said he had told underlings to investigate the matter but he has not revealed whether he, as is common practice in these matters, was ever interviewed to obtain his recollection of events.) And therein lies the problem.

If Cain and/or his campaign think they can say whatever they please and the media and public will simply accept it and go away, they are mistaken. Moreover, this behavior suggests an unawareness of, if not contempt for, the political process. At some point you have to stop insulting voters’ intelligence.

At this point we don’t know what Cain knows about his own past, let alone what he knows about the issues or the task of governing. And we are reaching the point where it is hard to tell if he knows, or his campaign aides know, if they’re telling the truth.

Iowans don’t need to believe he is innocent of sexual harassment to vote for him. But they do need to trust him. Virtually everything that happened yesterday with regard to this issue served to damage his trustworthiness. Beyond the point of no return? We’ll find out.

This should serve as a warning to all the vanity candidates (i.e., those without experience who run essentially as celebrities) in this and future cycles: A presidential nomination process is brutal and serious stuff. If they think there is no downside to competing, they are wrong. They may, at the end, come out diminished people, less respected and liked than when they went in.

Some people call this unfair and harmful to our political process. I disagree. If unserious and ill-prepared candidates try to take the voters for a ride, don’t bother to understand the issues or even their own weaknesses, they pretty much get what they deserve. And if voters bury their heads in the sand and vote for them anyway, they deserve what follows as well.

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