The presidents have their level of culpability for their decisions, certainly, But when W was told that their were WMD's, it painted a path for him to follow.
When the IC failed to paint the real picture with Afghany forces capabilities and behaviors, it also painted a picture that withdrawal could be accomplished reasonably.
I have said this before: Our IC department has had an incredibly bad track record. Incredibly bad. Over many decades. Not everything should be laid at their feet, but a good portion of it should imo.