*** I don't care much for religion. Spirituality? Yes. But "religion"? Nah***
Since spirituality means 'not tangible or material', belief in God is somewhat immaterial. It appears that all humans have an almost instinctive need for renewing the soul, holding something, anything sacred. Most of us opting for religion as vehicle for such.
You and I have rejected religion in general, yet replace it with another form of sprituality. Mine happens to be a belief in God, as manifested by his design of the world around us. I get the same renewal of soul, by looking at Half Dome in Yosemite National Park, or standing on the edge of the Grand Canyon, or walking through one of the giant seqouia tree's who have lived for thousands of years.
So people man conclude God does not exsist. But human instinct will always prevail, sprituality will prevail.
The madman/men who are on a killing spree in DC,,,,,have already answered your question. The very first clue, left at one of the crime scenes was a tarot card, with the handwritten assertion "Mr policeman, Iam God"