You should get out more. Maybe a trip to Syria or Iraq. There's some destruction being carried out by some very religious believers.
That religion, like most human institutions, can be twisted to serve evil purposes is a reality that I would never deny. But I do not blame the religion as much as I blame the innate nature of humanity.
Religions, though perhaps inspired by divinity, is fundamentally a human construct. It is intended purpose is to develop the better side of human nature, yet like all human constructs it is likewise subject to our darker side as well.
Is a knife fundamentally evil? No, it depends up on the intent and will of the user who picks it up. If used for its intent, it may create beautiful works of culinary art. If not, it may be used for horrific or destructive purposes.
You would eradicate religion and not eradicate one bit of the war and violence that plagues humankind. Justification for it would just shift to something else. But you would eliminate much of the principle and core of many religious beliefs which aims to instill respect for the human person as well as a reverence an awe for creation and its creator.
"Christianity has not been tried and found wanting; it has been found difficult and not tried." - Gilbert K. Chesterton
I wish I could talk more, but I must go for the day.