I just don't understand what problems you have with what I wrote. Did I say that I advocate 3D printer regulations? I don't. First I don't see that it can be regulated, second... I want to have one of those myself. Not to print guns, but all the other cool stuff. But a problem does not go away just by ignoring or denying it. Even though I am constantly told here how easy it is to build a working weapon with stuff from a hardware store, it is not easy. Not many people are skilled enough to build their own weapon from scratch. At least not many compared to the numbers when in a few years in almost every home such a printer stands. Unlikely? How many homes had a 2D printer 30 years ago?

Don't think so. Generally yes, something like this will happen. But at the moment such printers are far too rare as that the usual protection mechanisms are lobbied in.

Cunt.

Not necessary to sign a post here with your real name. 'zedtwitz' is doing fine as nick.

Hey dipshit,

You are confused, I am not your mother. For the rest what you said: Yes, high quality 3D printers are very expensive at the moment. But so where computers ~30 years ago. It can be expected that 3D printers will become much cheaper and much better in the next few years.

Replace 'Terrorists' with 'Child Porn'. Works better with encryption related fear mongering.

Metal working tools (also unregulated) have allowed a skilled backyard machinist to build weapons for probably the last 150 years.

That's the difference: skilled backyard machinist .
With those printers every idiot with two left hands can download the plans and print his gun. Probably even kids. So there is a new quality to what was possible for the last 150 years.

The ability to create a plastic/resin based shell casing that can properly detonate and propel a shell as required isn't possible.

Not? I wouldn't be too sure of that. Perhaps a shell made of stone? Not much precision necessary for the very short distances in a plane.

...the printer only starts if you put a drop of your blood into a receptacle. With the DNA in it the plastic material is 'signed'. Ok, I am not serious, but who knows...

Failure to do so might lead us to design legislation based on the form of a robot, and not the function. This would be a grave mistake.

What's new about that? In many countries drawn or even written child pornography is treated like the real thing. Even though no child is harmed. In a way legislation based on form, not on function. Grave mistake?

I do not doubt that professionals will continue to use Photoshop. But how many professionals are there? Whenever the Window/Linux, Photoshop/Gimp discussion starts one can quickly get the impression that 90% of all computer users are highly paid professionals, who really need Photoshop. Too bad that there are still old Photoshop versions available. I'd really love to see how those discussions would change, when it would be impossible to use Photoshop without paying for it.

Finally a chance for Gimp and Linux. I don't know how often I had to hear: I cannot switch to Linux, there is no Photoshop and Gimp sucks. I was always surprised how many professional graphic designers constantly hang out in all kind of forums to tell the world how bad Gimp is. Now we will see how superior Photoshop really is, when it cannot be copied anymore.

I am afraid this is a bit short sighted. 'Local hardware store' and 'few simple hand tools' are quite a hurdle for the usual left handed couch potato. Downloading a 'gun definition file' and filling some plastic pellets into a 3D printer are not.

I am not worried about Americans. They have enough not printed guns so that a few more printed ones do not matter. They are a spit in the ocean. I am worried what this will do in countries with sane weapon laws. And I am worried what this will do to 3D printers.

If you want bitcoins I suppose it would be much more efficient to ask your users to pay you in bitcoins for your app. If your app is widely spread enough and good enough, and even if only one percent of your users pay, it would most likely be much more than what you could mine.

Much (most?) of the energy from an ordinary nuclear bomb comes off as gamma rays.

Really? When an uranium or plutonium atom splits, fragments with plenty of kinetic energy are created. Even in an H-bomb high kinetic matter is created. There are no such fragments in an anti-matter explosion.

Because the atmosphere happens to be relatively opaque to gamma,

It is? Even lead is not relatively opaque to gamma rays. Not saying that you are wrong, I just don't know. It would surprise me.

Proton-antiproton collisions tend to produce gamma plus some secondary particles (pions (pi-mesons), if I remember right, but I may not

At least this part is easy to google and you are right. Of course, again a problem of quantity. How interact pions with the surrounding matter and how much energy they carry.