In my readings and understanding why the Crusades happened, it was to stop the spread of Islam. We as Christians are called to love our enemies and pray for those who persecute you (Matthew 5:44). So we as Christians should remain peaceful as often as we can. I think that part of the Crusades can be justified, because they are commanded to take the Holy Land, but I do not think it is Justifiable to kill Muslims because they are preaching a different religion. There are probably more peaceful alternatives to achieve their goals. I think today that the government could use Augustine’s Just War theory, because the main point is pacifism. War should be used to protect the innocent and not to achieve more possessions.