Oh if religion wasn't responsible for "massive cultural destruction" then mankind would have invented something else to do it (whatever is meant by "massive cultural destruction").

"We want their stuff" is a pretty effective travesty generator for sure.

I disagree. When you are absolutely sure that God itself is on your side, then there is no atrocity to big to commit. I feel that religious zeal has led to some of the worst catastrophes in human history. I would put para-religious zeal in that category too, like dogmatic forms of communism.