The FBI and INS failures are what led to 9/11. Anybody with half a brain knew that OBL was going to keep trying to kill Americans, the FBI/INS failed to follow up leads or make sure that people who shouldn't be here weren't here.
I don't think he left Bush out to dry either. I don't remember the exact words, but I don't think Bush stated that WMD were an imminent threat.
I don't think the war was about WMD or freeing the Iraqi people, I think it was about doing what should have been done in '91, but the politicians had to come up with something for the press (who were going to twist things different ways no matter what) and WMD were an easy claim. I'd bet that %99 of those of us on FR believe that between '91 and '03, there were WMDs in Iraq, and that Saddam, given the opportunity, would have funneled them or some other sort of assistance, to OBL, and I don't think any of us believed the Saddam would use them against the US directly.
It's an interesting situation, Bush can't come out and say "we are just doing what should have been finished in '91".
There is a lot of truth in that, I think. One problem here is that to most in the West, the Gulf War was "over" in 1991 because our governmental/legal apparatus said so. The problem was, we were still (a) blockading that country, (b) occasionally bombing that country, and (c) basing some troops in a neighboring country to protect against continued offensive moves.
By most rational standards, that's called a "war".
And the assumption that Saddam wouldn't have seen it that way because WE thought the war was "over", according to our legalistic definitions, is quite odd. The idea that Saddam would have taken blockading and bombing his country in good humor, and made no attempts to do something in response, is downright bizarre.
In fact everyone acknowledges that part of his attempt included waging a propaganda campaign designed to shame the West into dropping the sanctions because they had killed (precisely) 500,000 Iraqi babies.
People who complain that we launched a 2003 final offensive against Hussein should also take into account that if we hadn't done that, he was most likely going to win that propaganda campaign within a couple more years, as even the facade of sanctions dropped away.
After that point, it would not have been incorrect to say that Saddam would have defeated the US in the war between that nation-state and his, since (again, assuming we hadn't invaded and then the sanctions regime fell apart) he would have emerged unscathed, and in power, and in full possession of the oil assets of that country.
What he would have then done with the proceeds of those oil assets, and with no sanctions to constrain him, and given his hatred of the US and his reported desire for revenge, and given his powerlust and desire to rule over a pan-Arab state, I shall leave up to peoples' imagination. Speaking for myself, I am rather glad we did not wait around to find out.