I have never thought they were wrong. Rather, they were just. The Seljuk Turks had invaded and taken over half the (christian) Byzantine Empire 20 years previous, and were threatening Constantinople, the back door to Europe, and threatening to dominate the entire Mediterranean, and all trade within it. It was a strategic war for survival.
No, they were not wrong. I agree that they were just. There were some battles that were wrong, but the Crusades themselves were necessary. And these filthy animals have not progressed over all these centuries.