Actually we do hear of a massive increase in risk of the spreading of STDs such as HIV in men who are uncircumsized. As for evolution, as a biologist I enjoy the shout out, but the obvious advantage of the foreskin is to protect our penis, as we have been wearing clothes for only about a second on evolutionary time scales that argument is invalid. Why do we have underarm? Also if everyone in the world showered as much as American, we would just run out of water. This issue is complex.