Man perceives the world based upon his pre-conceived notions to organize the torrent of facts to fit his biases. An atheist, even if God were to apotheosise, will dismiss such event as neuronal malfunction. Similarly, a religious will not be convinced out of his belief system regardless of contrary facts to his pre-conceived notion of the universe. If you think "religion" was the cause of man's inhumanity to man, just consider the 65 million liquidated by the atheist bureaucrats of Marxist utopia during the short misrule of Stalin, Mao, and Pol Pot.

The only truthful aspect of humanity is that man has killed man since beginning of creation, and new technical and scientific advancements have and will only result in new places and ways, on and in which man will die. This is the immutable truth of this world and the human condition. Without a controlling, indoctrinating idealogy to enslave the creature called man, he will be eating his own children, even before the ink on the paper "emancipating" him from ideologic servitude is dry. For many slavery is a step up from their what they would have been. Without a supernatural force to restrain man's inherent inhumanity, a society will either devolve into cannibalism, or choose to preserve civilization by constructing a police state. Even if there were no God, it would be necessary to invent him.