For years seen as a losing battle, the push for gun control has become a central conflict of the 2016 presidential election, and part of a broader struggle between competing visions of policing, justice and racism in America. Donald Trump, the presumptive nominee of the Republican party, has pledged that if elected he will eliminate "gun-free zones" and make it easier to carry a concealed firearm in all 50 states. National Rifle Association members cheered him on... (GunPolicy.org)