If assault weapons who's only purpose is for war and fast, efficient killing of humans are your right to own and use then your rights should equally be to own and use hand grenades and missile launchers and everything ELSE!!!
You are incorrect in your assessment of assault weapons being killing machines. They are designed to be light, handy, accurate, easy to reload and shoot. Accuracy is in the eye of the beholder as they are not easily made into rapid fire sniper rifles. The military has many configurations for specialized uses. In addition, they were designed to be used by everyone with minimal training.
The military found in past wars that the average American was horrible with a rifle in their hands, they loved country boys that could hit a moving deer or rabbit. That is why the NRA was formed, to promote marksmanship more broadly, as it is to late to teach it when the need is already upon you.
In case you havn't noticed, the pirates in Africa have RPG's and Grenades and other such weapons. So do drug cartel's in Mexico. IF a gang or drug cartel or whatever you want to label them start using them in the US, are you going to call for them to be banned? They already are just like REAL assault weapons(full auto) It does not deter the criminals one bit, they just don't care.
You are just lashing out as YOU don't see the NEED for one. I havn't fired a full auto or ridden in a tank. But I could own them both if I had enough money, LEGALLY.
I should add that they were found to be lacking as a weapon in the open areas in Iraq and Afghanistan. The sniper corps made a big comeback and the need for a more powerful round at extended ranges was identified. The old 7.62 Nato(.308) was more desirable then the 5.56 Nato(.223) as the ranges were beyond the effective range of the 5.56.
So you see, all weapons are assault weapons, in a certain time and place. Just like arguing about what someone would or wouldn't do in a shooter situation. No to situations are the same. You gotta dance with the girl you brought to the dance.