I voted for GW twice. I would do the same thing.
I had serious disagreements with him over amnesty. I think he made a bad decision on Dubai Ports. But his worst decision was not defending himself in the media. They ate his lunch and that of his administration. I heard Cheney, I believe, about a year or so ago saying he now sees it as a mistake. It was more than a mistake. It was frustrating beyond measure.
In any case, I see no problem with Powell saying the spooks had bad info that they passed to him as good info. I can see a Trump listening to that kind of verification of the “No WMDs” meme that became doctrine everywhere eventually, and concluding that deceit took place.
Personally, I believe the deceit was the other direction. We found old WMDs, capability to quickly retool their WMD weaponry, recipes, and connections for precursors. More concerning to me always was the ability to produce small quantities of chemical weaponry and aerosolize it in small containers for terrorist distribution.
I NEVER feared terrorists shipping a major weapons system to the USA and attacking us with missiles or artillery. I was more concerned with a Raid can full of Sarin set off at a high school basketball game.
Fair enough. I got to see things from a perspective that most Americans don’t - and one I never thought I would have either.