Why is it hard to defend 3d printing and cryptography? Are those controversial as well?

Yes, among certain circles. California recently passed a law regarding 3D printers requiring that they not be used to make parts for firearms. To accomplish this they want all parts washed through a database of known firearm parts to send back a PRINT/DONTPRINT signal. In practice this is impossible. It would require the 3D printer always be connected to the internet AND be in cahoots with the backend database. Sure you can add features like signed firmware handshakes with the database using Encryption, but there’s nothing stopping the 3D printing world from buying their own devboards and using their own software to run the printer they bought.

With restricting Encryption it’s sold as protecting kids and preventing criminals from doing crimes. Who could be against that? Except the entire modern digital world depends utterly on encryption. If some savant woke up this morning and published a break to AES the entire world would grind to a halt because now financial transactions don’t have a security guarantee anymore. Arguments against limiting encryption usually boil down to a “backdoor” or “key escrow” if the article is being really fancy, but don’t use phrases like “remove security guarantees.”

So, my point was arguments for limiting encryption can sound good until you know something about encryption. Arguments about preventing 3D printers from making gun parts sound good until you know something about 3D printers, and arguments about banning firearms sound good until you know something about firearms. The 3D printing world should be taking notes from the mish-mash of firearms laws that applies to the US because that’s coming their way. Paying a lawyer to explain why ordering filament used to manufacture gun parts without having a registered 3D printing device doesn’t sound like a whole lot of fun, especially when the people you’re trying to convince don’t understand the arguments and don’t care.

Some links:

• The Polish were manufacturing weapons even while occupied by the Nazis
• Owning the parts to make an illegal weapon, even though they’re not assembled, can be enough to get you into legal trouble
• Another link on constructive possession because I didn’t like that first one enough
• Shoestring machine gun