There's. No. Such. Thing. Period.
Prophet Muhammad also said that it is obligatory for Ummah to take part in the lesser jihad when some Muslim community somewhere is under assault by the unbelievers.
This is a classic example of terrorism: killing a person for the sake of political beliefs, and attention to them.
The guys who did the killing are British citizens. If they identify with some other nation as "theirs", that would make it rather old-fashioned treason.
What you describe is actually something that I personally support. One thing that you didn't mention but which I think is implied is that everyone has access to that database via the query API in question (i.e. I, as a private person, can run the check on any one who provides me the necessary data).
The only problem with this idea is that, if you make running the checks legally required, how do you enforce that? If you give an "e-receipt" - a hash of some kind? - to the person running the check, and they're required to keep it to be able to prove that they did the check, it would work, but wouldn't it be an undue burden on the seller? On the other hand, does it actually need to be actively enforced? I'd imagine that if such law is in place, most people would run the checks (heck, most would probably run them without any law; I know I would), which may well be good enough, statistically speaking.
I actually spend most of my time around democrats, being somewhere to the left of party mainstream (though my gun-related activities also put me in contact with many right-wing folk, there's little else on which I and they have common points). A clear majority support magazine size restrictions. A lot would prefer to see all semi-autos and handguns banned, reasoning that bolt-actions are good enough for hunting, and pump shotguns are good enough for self-defense at home (and considering handguns to be dangerous enough to override their utility as a portable self-defense tool). And "just ban them all" is not limited to one or two weird guys, either.
I'll grant you that there's also a minority with a somewhat libertarian outlook on policies other than economics, but it's just that - a minority.
Moderate democrats these day are usually not in favor of 2A as an individual right.
GP is a libertarian, clear and simple.
I suspect she would choose to print statues of Mary.
Your Google account is a G+ account, it just has a bit flag "don't tell me about G+" set in it, courtesy of Google.
That sounds like a maintenance nightmare. The code you're writing and debugging is not the code actually running
When you're writing native desktop apps, the code that's actually running is also not the same as what you're writing and debugging - the former is assembly, the latter is C or C++.
I find it very dubious that the tech in question is actually viable today. I am not aware of any actual "smart gun" offerings on the market today, and surely there would be some if it could be pulled off in a reasonable way - there would be demand for them, if only among the casual gun owners who want an extra safety measure for the sake of peace of mind, even at the cost of reliability.
Well, we need some generic standard for push notifications first, and we need that standard to not require a centralized server - which kills it right away, since e.g. both Apple and Microsoft insist on people using its servers for all notifications on iOS, Win8 and WP8. Unfortunately, this whole battery optimization business resulted in a kind of lock-in for the new generation of high-level networking protocols.
Why not just sell them into slavery while you're at it?
Lead is trivially cast into bullets.
Black gunpowder is not hard to make, and, for all its disadvantages, can be used quite successfully in single-shot or manual-cycling designs (bolt/pump/lever-action), and even some repeaters (e.g. DAO revolvers).
Cases can be made out of plastic - see shotgun shells.
This leaves the primers. I don't know if these can conceivably be home-made, but I suspect it's not all that hard.
Anybody can create a gun out of a bunch of metal pipes and a couple of springs, all readily available in the local Home Depot, with as little as an electric drill. This has been true for decades now, too. It's just as untraceable, and you can actually make semi-auto (or even full-auto) weapons firing a decent-sized round that way. So, nothing new here, other than all the sudden attention.