>> As soon as 3d printers will be able to replicate themselves, every regulation will be moot.

> I don't get this. In theory, if it were illegal to print "Item #325" having 200 printers doesn't make it any less illegal to print "Item #325".

It might be illegal. But the law would be unenforceable.

>> Information always finds a way to propagate.

> Doesn't this presuppose that no secret has ever been kept?

Valid point. What I meant is information that is out in the open. The cad files by Defense Distributed where published intentionally. You need a North Korean style regime to significantly slow down the propagation of such material.

Most places you're not allowed to carry a knife in crowds. Doesn't really matter if you've made it yourself or not.

You're not? I know some places ban very specific elements of 'knifes' that have nothing to do with how pokey they are for political reasons, but there are areas that actually ban having a knife?

Well, the other question is whether it will be legal to manufacture/sell printers which are capable of printing illegal things. If the printers are capable of self-replicating it will be implausible to enforce that sort of regulation.

It is presumably already illegal to 3-D print several types of 3-D things, where such things themselves are illegal or where there is some form of copyright, trademark or patent infringement.

the only secrets are the secrets that keep themselves