Because as long as the Jihadists and their allies were getting positive help from the idea that “Bush lied” and “Intelligence was sexed up” and all of those media statements, they were unlikely to blow all of that positive press by using WMDs. Letting the misinformation stand, letting the enemy get a propaganda advantage out of using the misinformation, helped stop them using the weapons and blowing that advantage.
Better a politician be called a fool or even a liar, than soldiers die because he protected his reputation.
And they knew it would all come out in the end anyway.
I’m glad I am on this site to here from folks like you.