Bottom Line: Obama Cuts Ties With Rev. Wright

— -- Sensing no issue has threatened his campaign more than the controversy surrounding Rev. Jeremiah Wright, Sen. Barack Obama, D-Ill., used much stronger words on Tuesday against his former pastor than anything he has said previously.

"World News" anchor Charles Gibson and Chief Washington Correspondent George Stephanopoulos discuss Sen. Obama's extrodinary public divorce with his former pastor.

CHARLES GIBSON: George, Barack Obama has been judicious in his comments up until now about Jeremiah Wright. Jeremiah Wright yesterday at the National Press Club really didn't say anything different than he said in some of those sermons that have been played over and over again, so what changed with the Senator?

GEORGE STEPHANOPOULOS: It was on national t.v. Everyone could see it, Charlie. And his campaign realized this posed a mortal threat really to his nomination. It also - Rev. Wright yesterday left the impression that somehow Barack Obama secretly agreed with this - he was just being a politician.

Barack Obama couldn't afford to let that stand.

They were seeing this bleeding in Indiana and North Carolina. They were hearing from other superdelegates that Obama had to look strong. And then when Obama saw the performance himself he did get mortally teed off - that tipped the balance.

CHARLES GIBSON: Do they have any measure of how badly hurt he has been? I mean, I know the polls are down slightly but do they know this is doing?

GEORGE STEPHANOPOULOS: They're hearing from everybody. I mean, you know, this is something you know in your gut Charlie even if the polls don?t show you immediately how much damage you're taking. They know this is a big for them. But they're hoping now that Obama showed anger - controlled anger -that he said clearly that he's outraged by this that they can now move on and so that they can say they've said all they need to say about this.

CHARLES GIBSON: And it's knocked him off his message. It's knocked him off the things that he wants to be saying?