You can read the details here. I see no need to repeat them, and nothing is very surprising. Basically, McClellan admits he was an unwitting part of several manipulations and coverups, and of course he didn't know a thing about any of it, not a single, intsy thing. He was just there as a mere mouthpiece who went in front of the press and repeated what he was told like a good little puppet.
Do you want to vomit yet?
Men like McClellan are -- and always have been -- the enablers of misguided and dishonest leaders. They sacrificed the basic principle of human interaction -- honestly -- in order to be close to the center of power, to look important, to be someone.
Maybe to sell a few book afterwards.
Now he wants our sympathy. But if McClellan really wanted to be useful, really want to be an honest man, he could have came out in the middle of it all and told the truth. Sure, he'd lose his job. There are more important things in this world than jobs. If you haven't lost one on principle, you haven't really lived.
Now we're supposed to believe Scott McClellan, like he's some big hero for disclosing the "truth" years later when he's perfectly safe. Thus does corruption, dishonesty, and arrogance propagate through the centuries. It is sad. Like the day when war ends because all men refuse to fight them, corruption will end when all men refuse to cover it up.
Before they publish.