I think this entirely begs the question of our relationship to and with God, or vice versa. And another thread has been exploring this recently.
But to answer your question ... I think God is probably quite capable of defending "Himself." *Darn sure* a lot more capable than I am!
How *do* I feel? I think wil pretty much nailed it. If your left hand is securely grasping your "opponent" by the neck, while your right is lodged quite a ways down their throat holding either a religious tract - in one case - or a primer on materialistic, secular humanism in the other ... then you're both equally in the wrong. Two wrongs do not make a right. Another person's actions do not justify our own. Same is true of groups, ideologies, religions, etc.
Personally, I find atheism and materialism to be exceedingly bleak, mostly because they undermine the importance and value of the individual. Ironically, this notion of the celebration of humanity falls short, precisely because it fails to acknowledge our highest potential ... which is something thoroughly spiritual, in my experience and belief.
We are all entitled to our beliefs, thoughts, perceptions. Everyone sees things the way they see them for a reason. How do I know that this is not simply a part of their learning experience of the moment? Or to put it otherwise, How can I be certain that this is not God's Plan for them ... an important stage in their growth? Only if I am willing to stand up and say, *I know AS WELL AS (or better than) God* ... can I then condemn or judge.
~Zag