A religious argument about the existence of God took a tragic turn in San Francisco after 33-year-old Douglas Yim became so enraged at his atheist friend that he shot him to death. Yim and his friend, 25-year-old Dzuy Duhn Phan, had apparently spent a drug and alcohol-fueled night playing video games, when their conversation took a theological turn. It was a reportedly “heated” discussion, one that peaked with Phan asked Yim where God was when his father died of a stroke years ago. Yim snapped, grabbed his gun and shot Phan six times in the head. He’s facing 126 years in prison …