In the days after the shooting at an Orlando nightclub left 49 people dead and dozens wounded, the debate in Washington has turned to guns and terrorism. NBC's Pete Williams reports on the investigation and shooter. President Obama visited families of victims while after a 15-hour Democratic filibuster, senators will vote on four gun proposals next week. On the campaign trail, Republican Donald Trump renewed calls to ban Muslim immigration, but both Trump and Democrat Hillary Clinton have expressed support for "no fly, no buy" legislation.
