The riveting spectacle of human frailty captured on FBI videotape and aired worldwide last week shows D.C. Mayor Marion Barry as a clumsy but not mean man, more pathetic than desperate.

The tape makes it clear to me that Barry has a personal problem, with alcohol and cocaine. It also shows that Marion Barry is at war with Marion Barry. For the past 161 days, he says, he has been winning the war by staying drug-free.

But if this is true, it is only because his victories began that awful night of Jan. 18, when he lost a big battle to Hazel Diane "Rasheeda" Moore and the FBI.

From his early reluctance to visit Moore's room at the Vista Hotel, to his telling her, "I don't smoke no more, honey," until, finally, he smoked the crack, the hour and a half or so of Barry on videotape offers a textbook example of an addict's inability to just say no.

And because he is the District's chief executive, everyone's boss, it had become increasingly clear that no one could intervene with traditional methods of therapy.

There seemed to be no way other than arrest to stop him; Barry had turned all those around him into "enablers" and "co-dependents," in the language of addiction therapists.

Aside from the fact that the most humiliating experience in his life may have saved Barry's life, the FBI videotape offers a rare glimpse at what addiction treatment specialist Scott McMillin calls "the war within." It shows the futility of Barry's enormous willpower when he does battle with his compulsion for drugs.

"I have been so good lately, I surprised myself," he told Moore. A moment later, Barry blurted out, "Go get some."

The videotape is also instructive for those who are prone to fooling themselves, as Barry was. Hopefully, others will seek help for their drug and alcohol problems before they fall as far as Barry has.

"It is paradoxical that many addicts and alcoholics begin to develop a will to stop using and at the same time try to do so by asserting control over the substance," McMillin said. "They make vows and promises to themselves and others that they will stop. But the harder they try, the worse the situation becomes. It's like squeezing a greasy pole to get a better grip."

As the videotape rolls, Barry is seen as a troubled man, badly in need of comfort. He is anxious and weary, pouring himself cognac after cognac in a mind-numbing effort to relax.

He begins by talking to Moore as if she were his wife. A few minutes later, after the alcohol has slurred his speech, he is clearly in the mood for Moore. Barry talks of sex, but eventually he gives Moore money and sends her to fetch some crack.

According to McMillin, who heads the addiction treatment center at Suburban Hospital in Bethesda, Barry probably didn't know what had hit him.

So insidious is the nature of drug addiction that a person can easily be thinking about cocaine subconsciously. Without speaking of the drug, many crack addicts are known to hear what they refer to as "the call of the rock."

"Cocaine is a powerful, self-reinforcing drug," McMillin said. "You develop a conditioned reflex about people, places and things related to using cocaine and they become difficult to forget."

As they lay on the hotel bed, Barry and Moore talked at length about other people with whom they allegedly used drugs, laughing and joking as they recounted various drug-related episodes. If Moore's testimony that she and Barry have a history of drug use is true, then Barry's thoughts of sex and drugs probably began the moment he received the message saying that she was in town.

Standing in front of a mirror as he waited for Moore to return with the crack, Barry seemed to look himself in the eye, adjusting his suspenders and rubbing the bald spot on his head. Here he was -- a middle-aged married man being rebuffed by an aging, overweight ex-model. When Moore had removed Barry's hand from her blouse, his dejection became apparent.

"I can't caress your breast," he fretted softly.

Down on the bed Barry plopped, his shoulders drooping. There would be no sex.

Although he was the mayor, Moore was no longer impressed by his power to arrange live television interviews or the intrigue of his evading President Bush's security detail or the convenience of having his own walkie-talkie.

The disappointment apparently had left Barry ready for a crack-fueled mood change. But had Rasheeda Moore set him up -- or had he done it to himself?