I thought at first it was because I didn't explain it well enough

And didn't have the facts at hand. It took a long time to realize that those people who supported Bush and supported the war did not want facts. Did not want to be shown how wrong they were. Did not want to be shown how readily they had accepted the propaganda and the lies.

Phila of Bouphonia discusses Norman Solomon's idea that we need to deconstruct the lies: (my bold)

What Solomon overlooks is that political lies are successful not to the extent that they’re plausible, but to the extent that they’re preferable to reality. That’s why people who try to puncture political fantasies so often end up on the sidelines licking their wounds, while rampant and ululant liars continue to be treated with quasi-religious reverence. It’s not a lie if it’s what you want to hear.

Solomon’s assumption – which is very common on the left – is that it’s a simple lack of information that causes Americans to support, or at least tolerate, criminal policies. That’s true in the sense that it’s a simple lack of information that prevents compulsive gamblers from believing they’ll beat the odds, but false in its rationalist assumption that given a choice between fantasy and truth, people will (or are able to) choose the truth. What truth more often produces, as we all know, is an overwhelming immune response whose chief symptom is rage.

That's why the anger generated by stating the truth is focused back on the truth-tellers. That's explains the smears and the slander, the ugly mockery, the hate speech. The Bush supporters are desperately shielding their fantasy world from the brilliant light of reality. And losing....