In an interview with the New Yorker, President Obama says that he believes marijuana is less dangerous than alcohol.
From the lengthy article:
When I asked Obama about another area of shifting public opinion—the legalization of marijuana—he seemed even less eager to evolve with any dispatch and get in front of the issue. “As has been well documented, I smoked pot as a kid, and I view it as a bad habit and a vice, not very different from the cigarettes that I smoked as a young person up through a big chunk of my adult life. I don’t think it is more dangerous than alcohol.”
Is it less dangerous? I asked. ...
Less dangerous, he said, “in terms of its impact on the individual consumer. It’s not something I encourage, and I’ve told my daughters I think it’s a bad idea, a waste of time, not very healthy.”
Also in the same article, President Obama says that if he had a son, he wouldn't let him play football.
Obama spent his flight time in the private quarters in the nose of the plane, in his office compartment, or in a conference room. At one point on the trip from Andrews Air Force Base to Seattle, I was invited up front for a conversation. Obama was sitting at his desk watching the Miami Dolphins–Carolina Panthers game. Slender as a switch, he wore a white shirt and dark slacks; a flight jacket was slung over his high-backed leather chair. As we talked, mainly about the Middle East, his eyes wandered to the game. Reports of multiple concussions and retired players with early-onset dementia had been in the news all year, and so, before I left, I asked if he didn’t feel at all ambivalent about following the sport. He didn’t.
“I would not let my son play pro football,” he conceded.