Unless you're the sort of person who's easily alarmed, perhaps because you find it expedient to be alarmed and want to get other folks running in tight circles too, the now-infamous William C. Ayers of Chicago, Ill., just doesn't seem like a particularly scary dude.

Barack Obama is being pilloried by partisan vigilantes for having associated at some modest level with Ayers, who used to be active in the violent, Vietnam War-era Weather Underground radical protest group.

There's obvious desperation at work here. With the economy and the stock market sinking 1929-style, Republicans grope for some issue to take people's minds off the fact that the crisis occurs with a Republican in the White House and with John McCain failing to instill confidence that he can right the ship.

And when hollering about Obama's Ayers association doesn't give his foes the result they're looking for, they accuse him of a cover-up. They accuse him, in fact, of palling around with domestic terrorists, in Sarah Palin's slime-slinging formulation, and then lying about it. The implication is that Obama secretly hankers to go bomb a government building right now, or that he'd cheer if someone else did.

It's a disgusting line of attack, as insulting to voters as it is to Obama himself. No wonder McCain didn't mention it when face to face with Obama the other night. He would have been ashamed. (At a rally on Friday, the crowd of Obama-haters acted so appallingly that McCain was driven to come to his opponent's defense.)

The things Ayers did or helped do or favored as a Weatherman were "detestable" (Obama's word). But it is an outrageous leap to lay Ayers' past sins in Obama's lap simply because the two wound up active in some of the same perfectly respectable Chicago circles.

Obama may wish he hadn't attended a political event at the home of Ayers and his wife, Northwestern University law professor Bernardine Dohrn, another bad actor in the Weather Underground, when he was preparing to run for the Illinois Senate in 1995. But given Obama's rising political-legal career and their mutual home base in the university community of Hyde Park -- where the wacky right and wacky left exist side by side -- it's not surprising that he came to know Ayers and have some dealings with him.

The New York Times recently explored the Obama-Ayers relationship in some depth. Scott Shane's piece concludes that Obama has "played down" his link to the former outlaw radical but that the two, 16 years apart in age, "do not appear to have been close." Certainly they became acquainted long after Ayers, son of a former head of the power company Commonwealth Edison, had rejoined polite Chicago society.

No criminal charges ever stuck against Ayers, although there's no question he was involved in some bad business. Having emerged from the tumultuous years of protest, in 1987 he earned a doctorate in education at Columbia.

He landed on the faculty of the University of Illinois at Chicago, where he now is a professor of curriculum and instruction. He has written extensively on education themes. "He's done a lot of good in this city and nationally," Chicago Mayor Richard M. Daley told the Times.

An Obama spokesman recounted to the newspaper that Obama and Ayers first met in 1995 through an education project called the Chicago Annenberg Challenge. Obama became head of a board that doled out project grants. Ayers evidently helped put the money to use in classrooms. The two men also served from 2000 to 2002 on the board of the Woods Fund, a charity that had backed Obama's community organizing work in the 1980s.

Let's stipulate that Obama was willing to be in the same room with Ayers and that they shared some goals. Hasn't McCain ever sat in the same room with people whose past views and actions he didn't endorse -- for instance, Vietnamese with whom he hoped to bring about a post-war reconciliation?

Obama's critics say that Ayers' concept of school reform, with an emphasis on teaching social justice, veers unacceptably toward the radical left. OK, argue it out. But absent any evidence that Obama himself has a radical bone in his body -- no, don't bring up his membership in the Rev. Jeremiah Wright's church, because the test should be what Obama himself says and does, not what his pastor said and did -- it's time to stop with the character smears.

The McCain camp asks with a sinister twist, who's the real Barack Obama? It's a loaded question meant to impugn his mixed heritage, his rapid and unusual rise and his emergence from a cutthroat, big-city political environment. But surely the answer is not to be found in his relationship, such as it was, with the once criminally deluded and perhaps still wackily idealistic Bill Ayers.

Get $150+ in coupons in every Sunday N&O. Click here for convenient home delivery.