I don't usually post in this part, but wow, I just have to step in.
First, attributing religious wars and political strife as being waged under God's name is completely short-sighted, not to mention misinformed. For one thing, religion is a psychological construct. It means that people create it to feel good about themselves. Whether to bring them together (as was it's use for early communities of persecuted people) or to explain a common belief (as demonstrated by tribal religions). That said, bisan pa wala'y Kristiyanismo, or any Religion for that matter, na nahimo during all those wars, people would have still found a way to bring people together under a common goal, and wage war under it's name instead.
A simple study of history will tell you that the crusades wasn't for God. It was a political war that used religion -and God- as a scapegoat.
Stop blaming wars on religion or gods. We have enough to worry about.