Your larger point stands, that Christianity is often used as a weapon of sorts. The same goes for most religions, ideologies, and philosophies, even Buddhism is used to justify violence.

However, most religions themselves are generally peaceful. I'm convinced that Islam is peaceful, despite it being used to justify terrible acts of terrorism, gruesome punishments for deviance, etc. The same goes for communism and capitalism, which have both been used to justify violence (though I have a harder time with facism, it's just built on hate imo).

The enemy here isn't religion, but extremism. Even if we eradicate religion, we'll still have the propensity for extremism. The same people that use religion to justify violence would simply use something else instead. Most people don't fully understand their religion, ideology, or philosophy, and they don't seem to care, provided they get the results they want.

I hope that makes sense.