The Crusades were also a response to Arab invasions into Europe, during a time when Vienna, practically the center of Europe, was besieged
twice by the Ottomans, and the entire Iberian peninsula was conquered and held for more than half a millennium by Muslims (and Constantinople/Istanbul still is). Many border countries had children regularly kidnapped into slavery by Ottoman raids (or had to turn them over as part of the blood tax), then turned into child soldiers and made to participate in those same raids, so try to understand when not everyone shares your black and white view of crusaders.
Look at it this way - complaining about the Crusades makes as much sense as complaining about Purim, which celebrates 75 thousand Persians being pre-emptively killed for being "enemies of the Jews".