Even without the magical and little-known technology called 3D printing, the recent efforts at gun-control in the USA are doomed. 3D printers are readily available and getting cheaper. Some models can be had for $1200. Either effective gun control is dead, or the United States will soon evolve into a police state where everything is forbidden except that which is explicitly permitted. It was not very long ago that the former Soviet Union licensed photocopiers, and illegal possession or use of a photocopier could lead to extremely unpleasant consequences. Ask any ex-Soviet and they will explain that that control measure did not stop the spread of underground printed literature.
Here is the link to the story: