Muslims are violent because the idea of violence and bloodshed as a tool is still very recent in its history of conception. Much like Christianity in the early days. I am optimistic that as literacy rates increase and economic conditions around the world get better, Islam, too, will undergo progressive reforms that will be adopted by the mainstream followers.
But then again, I have been optimistic for a while now ...
"Eternal suffering awaits anyone who questions God's infinite love." - Bill Hicks