As I said before, these questions are borne of a profound ignorance of firearms, which is quite common. As such, these questions coming from progressive anti-liberty folks are really rhetorical rather than truly innocently inquisitive.
But, I'm going to pretend I'm having the conversation with someone.
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One: How many of you would chose an AR platform over a hand gun or shotgun for self-defense?
Rhetorical translation: Nobody needs an AR-15. It's not a good defense weapon (because I've heard that so many times in the media.)
My answer: First, I should point out that the AR-15 has no magical or special qualities that make it different from any other semi-automatic rifle. The AR-15 has great ergonomics, in that it is lightweight and adjustable to fit a variety of shooters' body types. But, it FUNCTIONS EXACTLY like every other semi-automatic firearm... a technology that is over a century old.
So... It depends. Which firearm I would consider "ideal" varies, depending on the situation. Please describe the context of the self-defense situation. I would choose different defensive weapons for different situations. Where am I, for example? Please provide some details of your hypothetical scenario that requires I defend myself. Be specific. Where am I? Who am I with? Who is attacking me? How many are attacking me? What time of day / night is it? Then, maybe I can answer your question in a qualified manner.
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Two: Besides a self-defense, what else would/do you use ARs for (fun/hobby; militia/against gov't tyranny; other)?
Rhetorical translation: Why do you "need" an AR-15? Nobody needs an AR-15.
My answer: That's an interesting choice of words and order of words. Let me ask you a question. Why SHOULDN'T I have an AR-15 or similar firearm? (pause and wait for the answer)
I have all my firearms for the same reasons, none of which require any justification... any more than I should justify my Right to Free Speech or to Peaceably Assemble or be Secure in my Person and Possessions.
But, if you really want to know, I can cite many excellent and practical reasons to own firearms. I own many different firearms, each of which fits a particular niche... kind of like shoes. Different shoes for different activities, right? Sneakers vs dress shoes vs running shoes vs hiking boots. Firearms are similar in that regard.
That said, I can do many things with a firearm. I can hunt and provide food for my family. I can defend myself and my family. I can engage in a multitude of competitive sports (marksmanship is one of the oldest / original events in the Olympics). I can shoot targets recreationally. Working on firearms, as a mechanical device, is as enjoyable as wrenching on a car. It's a hobby that I can share with others, which forges many excellent friendships. It's very social. Come with me to the range, and you'll see. But, yes... the origins of the 2nd Amendment are SPECIFICALLY rooted in the desire to prevent government tyranny. The Founders were brilliant and prescient.
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Three: Do you support any limits on ARs? If so, what are they? And, how much would you be willing to give up, in terms of what you can own, in light of other people shooting others?
Rhetorical translation: Why don't you support "common sense" restrictions on your ability to own and use firearms? You are obviously unreasonable and selfish.
My answer: I am not willing to give up ANY of my Constitutional Rights. Ever. Period. My Constitutional Rights are subject neither to the democratic process nor to arguments grounded in social utility.
I took an oath to support and defend the Constitution of the United States and pledging my very LIFE to that end by voluntarily serving as an officer in the U.S. Navy. The oath does not expire.
I took that oath with absolute knowledge and sincerity. It was not a "formality," nor was it "symbolic." It was fucking real. The person administering the oath was serious. I was serious when I took the oath. Having served is one of things I am most proud of. When you pledge your life to defend the Constitution, you tend to take it seriously.
I think it's important to point out that my oath was to defend the CONSTITUTION. Nowhere in the oath does it mention defending my country. Nowhere in the oath does it mention defending the flag. Nowhere does it mention obeying orders. It specifically says I will defend the CONSTITUTION against ALL enemies, foreign AND domestic.
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Four: Since the law of the land is that this right is not without limits (see Heller, p54), what rule or limit would you create on what ordinary citizens can own and not own (without reference to who should be able to own a gun and, separately, where guns should be allowed). Think broadly, because one of my colleagues made the argument, "Well what if bazookas become the norm for defending your house?" Some struggled in creating a rule distinguishing a long gun from an RPG—partly because they didn’t know the difference.
Rhetorical translation: I routinely engage in logical fallacies to make my point (rhetoric). In this case, the logical fallacy is "reductio ad absurdum" (an extreme form of straw man argument). Tanks, nuclear bombs, RPGs, and everyone's favorite... the BAZOOKA!
My answer: I would not create any limits on the 2nd Amendment, just as I would not advocate for limits on ANY of our Constitutional Rights. Why should there be limits? Should there be limits on Free Speech? What about limits on being secure in your person, property, or possessions? Should there be (air quotes) "reasonable" limits on your Right to trial by jury? What about limits on protections against cruel and unusual punishment? Are there exceptions to the 8th Amendment?
There are no limits on Free Speech. (This is how I set my trap. Invariably, they display their ignorance by regurgitating the old canard, "You can't yell 'fire' in a crowded theater." Of course, this is utterly and provably false. And, I admit taking great pleasure in blowing them out of the water with a truth bomb that reveals them as the unthinking, false talking point-regurgitators they are. I explain that they are suggesting Prior Restraint exists and is legal. It isn't. It's a hell of a lot of fun to watch the stunned silence that follows, as a result of the inevitable cognitive dissonance the truth elicits.)
Accordingly, I would never advocate for limits on the 2nd Amendment. It is just as important as the other Amendments.
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OK... I think that's enough!
Well, I was getting ready to type a lengthy response to the OP, but this is beautiful and mirrors close to what I was going to say. Well done, sir.