President Barack Obama marked the anniversary of the Newtown school shootings on Saturday by calling for tighter gun control and expanded mental healthcare, and by lighting 26 candles to commemorate the victims. "We haven't yet done enough to make our communities and our country safer," the president said in his weekly address. "We have to do more to keep dangerous people from getting their hands on a gun so easily. We have to do more to heal troubled minds." Obama did not mention the shooting at a Colorado high school on Friday where a student armed with a shotgun wounded...