In his first TV appearance since his ouster from Current TV last week, Keith Olbermann told David Letterman on The Late Show Tuesday that “I screwed up really big.”

“Let’s just start there,” said Olbermann, according to an early transcript provided by CBS. “I thought we could do this. It’s my fault that it didn’t succeed in the sense that I didn’t think the whole thing through. I didn’t say, ‘you know, if you buy a $10 million chandelier, you should have a house to put it in. Just walking around with a $10 million chandelier isn’t going to do anybody a lot of good, and it’s not going to do any good to the chandelier.’ And then it turned out we didn’t have a lot to put the house on to put the chandelier in, or a building permit, and I, I should have known that. And it is, it is my fault at heart … Now, I’ve been in situations in my lifetime where the second I agreed to something, I got that sinking feeling in my stomach and I said to myself on those occasions, ‘Holy goodness, I’ve just made a huge mistake.’”

Did that happen to you?” Letterman asked.

“It did,” Olbermann said. “In that situation, what you’re thinking is, ‘Oh, Lord, this is probably going to hit the water at some point,’ but what do you do? You have – you could bail out and say I’m getting out of this immediately,’ and trust me, I was thinking about that as early as like last July. We’d been on the air about 10 days and they fired the guy who knew what he was doing who I worked for and I went, ‘Uh-oh.’

“But I went home and just sort of had a conversation with myself and said, ‘Look, these – the two important groups that are more important than what I do about myself – the audience who, you know, went to struggle to find where the network was and join me, and, most importantly, the staff.'” Olbermann continued. “And I had 25 people who, most of them came with me from other jobs, one guy was with me four different places, and they put their careers at risk for me, and I didn’t even get a chance to say goodbye to them let alone thank them for the work that they did with me, and I’m, you know, I’m so proud of them because the show editorially was never better, but I let them down because the thing didn’t continue.”

Current TV released a statement saying it parted ways with the outspoken liberal news pundit, citing a difference in values. Olbermann shot back with a statement of his own saying “for more than a year I have been imploring Al Gore and Joel Hyatt to resolve our issues internally, while I’ve been not publicizing my complaints, and keeping the show alive for the sake of its loyal viewers and even more loyal staff.”

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