Copyright isn't really a problem. Which black smith had the first patent on the scimitar? Who patented gun powder? The wheel?
as for guns. more than 900 million guns exist in the world right now. and Less 0.001% of which will be used in violence against another person, If you include accidents and suicide the number might roughly triple.
The boston marathon bombers show us that restricting access to guns won't stop those who want to kill and harm, and those are the only ones we are worried about... right? I mean honestly are people just scared of a thing that has a lower risk of killing you or anyone you know than a hammer? Or are we going to be a bit more logical about this and make the point that gun crime is the issue not the existance of guns in general.
As soon as we resolve that issue we can figure things out better.
I honestly don't know what people are thinking is going to happen. As if that genie is ever going back in the bottle. Please. Pick a country that prevents the citizens from owning guns, then tell me nobody in the country has guns. No mafia member or immigrant extremist has ever had a gun. No gun has ever crossed into the country illegally.
Guns are here and they will likely remain for a great many more centuries to come. The worlds had crap for luck getting rid of drugs, and crafting meth is a hell of a lot harder to do than making something that will fire a bullet without exploding and killing the shooter too. But likewise just because drugs can be made at home doesn't mean everybody everywhere is a hopeless addict and pushing to kids to destroy their lives.
Finally, lets be very realistic here. The 3d printed guns that fire more than a few shot, they are printed in pieces inside a specilist type of 3d printer that costs several thousand dollars. Nobody alone in their apartment with a grudge and impulse will be able to finance such a device and it's specialty materials it needs to print with, and then spend the months researching the parts and designs to the detail level needed to print them, then spend the week printing the parts, another few days lubricating them, and assembling them in the right order. then they still have to buy the rounds for it.
With a few hundred bucks you could get hand tools and a book that would give you all the info you need and between hand machining stock from metal suppliers and parts that would suffice from a hardware store you could make a gun in under a week.
The only reason anybody hears about printing guns if gun phobes freak when they hear it, and gun humping loonies militantly over react when the phobes over react. If people weren't flipping their shit about the potential to print gun parts, gun nuts wouldn't bother with attempts to make plans free and get attention for being able to print guns. It's just one big "Are Too!" - "Are Not!" Shouting match, where every side is more conscerned with the fact that there is more than one side in the discussion than with any real facts or common sense.
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