There are three things in the world that you should recognize will not happen in this lifetime. You will not become a billionaire. The Cubs will not win the World Series. And John McCain will not explain his warm association with a notorious political criminal.

McCain has attacked Barack Obama for his connection to former Weather Underground member William Ayers, who in his words "was unrepentant over his activities as a member of a terrorist organization." In the final debate, McCain said that "we need to know the full extent of that relationship."

But though he thinks it's terrible for Obama to associate with dangerous militants, he thinks it's fine for him to do the same thing. And he'd rather go back to the Hanoi Hilton than disclose "the full extent of that relationship."

The extremist McCain has befriended is Gordon Liddy, who got a 20-year prison sentence for multiple felonies in the Watergate scandal — including burglary, conspiracy and illegal wiretapping. Finally forced to acknowledge the connection in an interview last week by David Letterman, McCain ducked and dodged before replying, "He went to prison, he paid his debt, as people do. I'm not in any way embarrassed to know Gordon Liddy."

Pressed further, McCain said he was ready to furnish what he asked of Obama: "Everything about any relationship that I've had I will make completely open and give a complete accounting of." Sure he will. Right after Sarah Palin becomes a Rastafarian.

After the Letterman interview, I repeatedly e-mailed campaign aides Tucker Bounds, Jill Hazelbaker and Mark Salter with several questions about the association. Their response? The same response I would have gotten had I e-mailed a trio of wax dummies: silence.

This leads us to some inescapable conclusions. The first is that McCain lied when he promised to lay out his relationship with Liddy. The second is that he is hypocritical in demanding something of Obama that he won't do himself. The third is that he is scared to tell Americans the truth because they won't like what they hear.

He's probably right. Liddy is not someone most of us would want to see visiting the Oval Office. Working for President Nixon, he committed a raft of crimes to secure Nixon's re-election and punish his perceived enemies. He proposed to do still more — bomb the liberal Brookings Institution, kidnap anti-war activists and murder a couple of inconvenient people. But cooler heads prevailed.

What does any of this have to do with McCain? Plenty. Liddy held a fundraiser at his home for McCain's 1998 Senate re-election race. He agreed to speak at another McCain fundraiser in 2000.

He has given several large contributions to McCain, including $1,000 this year. He has hosted McCain on his radio show, where the Arizona senator gushed, "I'm proud of you."

McCain says Liddy paid his debt, as if that erases everything. Actually, most of the debt was forgiven by President Carter, who commuted his sentence. McCain doesn't mention that, like Ayers, Liddy has never repented of his crimes, but takes pride in them.

His contempt for the law has not abated. After the 1993 raid in Waco, Liddy urged lethal violence against federal agents. "Now if the Bureau of Alcohol, Tobacco and Firearms comes to disarm you and they are bearing arms, resist them with arms," he told listeners. "Kill the sons of bitches." Only a year later did he amend his remarks to recommend that citizens not shoot unless they are shot at — which would have been a great comfort to any ATF agents gunned down in the meantime.

But don't take that as a sign that he's changed his ways. Liddy, who as a convicted felon is forbidden to possess a firearm, has bragged about keeping guns in his house and using them for target-shooting. When I asked the Bureau of Alcohol, Tobacco and Firearms what an ex-con could get for firing a gun, even at a target range, I was told it's a crime punishable by up to 10 years in prison.

For at least a decade, this unreformed criminal and enemy of democracy has been McCain's loyal friend, supporter and contributor. It may be a mystery just why the Republican nominee consorts with a lawless radical. But it's no mystery why he doesn't want to talk about it.

Steve Chapman blogs daily at newsblogs.chicagotribune.com/steve_chapman. To find out more about Steve Chapman, and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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