"...in your relationships. A gentleman named William Ayers. He
was part of the Weather Underground in the 1970s. They bombed the Pentagon, the Capitol, and other buildings. He's never apologized for that. And, in fact, on 9/11, he was quoted in the New York Times saying, "I don't regret setting bombs. I feel we didn't do enough." An early
organizing meeting for your State Senate campaign was held at his house
and your campaign has said you are "friendly."
Can you explain that relationship for the voters and explain to
Democrats why it won't be a problem?
OBAMA: George, but this is an example of what I'm talking about.
This is a guy who lives in my neighborhood, who's a professor of English
in Chicago who I know and who I have not received some official
endorsement from. He's not somebody who I exchange ideas from on a
regular basis.
And the notion that somehow as a consequence of me knowing somebody
who engaged in detestable acts 40 years ago, when I was 8 years old,
somehow reflects on me and my values doesn't make much sense, George.
The fact is that I'm also friendly with Tom Coburn, one of the most
conservative Republicans in the United States Senate, who, during his
campaign, once said that it might be appropriate to apply the death
penalty to those who carried out abortions.
Do I need to apologize for Mr. Coburn's statements? Because I
certainly don't agree with those, either.
So this kind of game in which anybody who I know, regardless of how
flimsy the relationship is, that somehow their ideas could be attributed
to me, I think the American people are smarter than that. They're not
going to suggest somehow that that is reflective of my views, because it
obviously isn't.
CLINTON: Well, I think that is a fair general statement, but I also
believe that Senator Obama served on a board with Mr. Ayers for a period
of time, the Woods Foundation, which was a paid directorship position.
And, if I'm not mistaken, that relationship with Mr. Ayers on this
board continued after 9/11 and after his reported comments, which were
deeply hurtful to people in New York and, I would hope, to every
American, because they were published on 9/11, and he said that he was
just sorry they hadn't done more.
And what they did was set bombs. And in some instances, people
died. So it is -- I think it is, again, an issue that people will be
asking about. ...."

http://blogs.suntimes.com/sweet/2008/04/democratic_philadelphia_debate.html