When you say "by Christians", do you mean by anyone who called himself a Christian regardless of his motive, or people who killed because it was their honest interpretation of the Bible that God wanted them as Christians to kill? Is there a real difference that we are aware of? In both cases, it is the individual who decides.
As I mentioned to several other posters, Muslims will decry violence committed by other Muslims - if that violence is perceived as "unpopular" in today's PC culture. That doesn't wash as far as I'm concerned. So if we are true to that standard, then claiming the Christians who committed violence weren't acting "in the spirit of Christianity" doesn't make it either.
Sorry if you disagree.
You know, this thread is not supposed to be a debate about what violent acts may or may not have been perpetrated in the name of Christianity. It is obvious that you have absolutely no idea what the definition of a true Christian is and seem to have some kind of axe to grind.