If you modify your car to be super fast and all that stuff, you have that right. However, society has deemed that if you make it so it's not street legal, you definitely are a danger to society. That's why there's a law against it. It's not about the intent, it's about what's good for society.
Essentially, it's not about what you plan to do with an AR-15(or similar weapons), it's about what could potentially happen if it's unleashed on public property. See what I mean?
I think most people that know even the slightest about guns can tell the difference between a handgun, a hunting rifle, and a weapon that looked like a soldier just dropped it on the ground. The latter is the "assault weapon" that people refer to. I'm not trying to sound condescending, but one of these is not like the other. It's not about semi-auto, it's about the ability to generate a lot of shots in a short amount of time, with a minimal amount of effort from the shooter(if trained). There's a massive difference between shooting a semi-automatic handgun, with both arms outstretched, and a semi-automatic "assault weapon" that you can cradle without nearly the same amount of recoil.
These kinds of weapons are great to shoot for the gun enthusiasts. Probably a huge thrill I'm sure. But is it necessary to own one? What's wrong with limiting the use of them to registered gun shops with firing ranges? It doesn't need to sit in your house waiting for something really bad to happen. You're not going to pick it up and mow down the one intruder coming into your house. Handguns and standard rifles handle that task very effectively.
Basically, for rabid gun owners, the question is - when is the firepower you can obtain "too much"? I say the limit is when the line crosses from home protection/hunting to "this is cool to fire and act like I'm a soldier". I have no problems with handguns and rifles. It's the military-grade stuff that's used for military purposes that crosses the line for me.
I didn't see at as that. It's a spirited discussion. At least you didn't call me a super liberal that wants all your guns.
I just think "assault weapons" are a bridge too far and simply excessive for people to buy. I don't even want to limit their exposure to them. Just the ownership of them. Keep them secure in gun shops/firing ranges, where you can go rent a session with them and go to town. That way someone doesn't flip their lid and go shoot up a theater or a school because life sucks for them. Sure, they could have a 10-round handgun that they have to reload, but the carnage would be smaller. Even that Loughner guy with his handgun and 30-round clip was subdued. Not to minimize their deaths, but he inflicted 14 casualties(6 deaths). Imagine if he had an AR-15.