This seems like just an inevitable issue with 3D printers. Give people the ability to print any object, and they're going to print things you maybe didn't want them to, like weapons, replicas/counterfeits of things you're selling, drug paraphernalia, etc. It can't really be prevented, and especially if you start trying to prevent the production of weapons, you get into the can of worms of "what constitutes a weapon, anyway?" - a screwdriver, a baseball bat, a shard of broken plastic are all usable as weapons.

To me it seems like the same kind of paradigm change as home taping and then the internet brought to the media industry. Now you can no longer profit off of (or control) the distribution and reproduction of media (or guns), because the consumers can do it without you being involved. There's not really anything you can do about it (despite what a lot of media companies seem to believe); you need to adapt.

I'm looking forward to advances in 3D printing, when someday we can print our own cables and adaptors instead of paying ridiculous markups for them (if they're even made), entire PCBs, etc. But those advances will also enable people to make more unsavoury things, too. It's a tool, like any other; whether it's used for good or bad depends who uses it. Context is important too: a guy printing syringes in his basement is probably bad, but hospitals could benefit greatly from being able to do that.

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