Once the Congress threw the decision into Bush's lap they then would support Bush's decision whatever it might have been, but it was still Bush's decision.
Go back and read the comments by the Democrats before casting their votes. THEY - some of the same big Liberal politicians we have today, a former President, and key Democrats - MADE THE CASE for going to war, CALLED FOR going to war, and insisted Hussein had to be overthrown. It wasn't just a vote to go to war if necessary - some of the Democrats made the case from the floor of Congress on why we HAD to. So don't try to minimalize the Democratic party's role in the decision to go to war. Don't make excuses and try to make it sound like going to war was not what they signed up for. They did!
Not many people will remember this, but after Hussein invaded and took over Kuwait, Bush sent troops in to liberate Kuwait, to drive Hussein back into Iraq. The Democrats opposed the move, criticizing Bush and the military operation big time for doing it. The American people, however, rallied around the troops and greatly supported the move. WEEKS after that war started Democrats in the house voted to AMMEND Congress' historical record (cook the books) to show that they had supported it from the start. (CNN reported it at the time) The Libs didn't want the next election coming up and have on the record that they had been against this highly popular move to liberate Kuwait. That's both funny and PATHETIC as hell....
Liberals always want to be on the 'winning' side. If it turns out what they supported ends badly they will insist they were never 'for' it but instead 'went reluctantly along'. If it's something they opposed from the start but ends well, they will claim they were for it from the start. When this is pointed out they will deny the hell out of it. They shouldn't....it's not a totally 'liberal' thing. It's a 'career politician' thing....and their ranks are full of them, too - just as the GOP is. So, 'embrace the suck', boys and girls. No one has the right to attempt to take the 'moral high ground' in this or many other cases.