The invasions were originally called "pilgrimage and holy war." After some time they were called "Crusades" because participants wore the cross on their tunics. Some participants may have had sincere Christian motives, but many of the leaders were motivated by ambition and greed--especially young aristocrats who could not inherit their fathers' titles and estates. The clergy who accompanies them spoke of doing mission work, but they did not have much success. Popes sanctioned these pilgrimages and regularly granted indulgences to those who participated. Thus there was more than a little work righteous motivation.

All in all, the Crusades were not a credit to the Savior, his gospel, or his church. Lutheran Christians did not participate in the Crusades and have no reason or need to defend them.

It is not likely that your youth group is motivated by politics, greed, or work righteousness. Nor is it likely that you will take violent action against those who do not agree with you. More likely, your "Crusaders" represent and bear witness to the cross of Christ and what Jesus accomplished there.

Incidentally, those who rail against the West and Christianity because of the Crusades forget or have never known that Muslims (particularly Arabs) invaded and warred against and subjugated Christian lands and peoples in Mesopotamia, Syria, Palestine, Egypt, North Africa, Sicily, Spain, and France about 400 years before the First Crusade. That activity was known as "jihad"--holy war.