You and I want the same things: Safety, freedom, prosperity, peace, and liberty. We may disagree about how to reach those goals, how they are prioritized, and even what they look like.
You ask, "Who 'needs' an AR-15?"
I need an AR-15 because you will not be made safe by leaving me defenseless.
I need an AR-15 because if I am disarmed you cannot guarantee my safety, however I will guarantee you are NOT made safe when I am disarmed.
I need an AR-15 because my safety is my responsibility.
I need an AR-15 because police have no obligation to respond to calls for help. (Gonzales v. Castle Rock, Warren v. District of Columbia, DeShaney v. Winnebago County)
I need an AR-15 because sometimes cops refuse to respond: (Reginald Denny, 1992 LA Riots; Broward deputy Scot Petersen)
I need an AR-15 because even when cops want to and have the ability to respond they may not arrive for 10 minutes. Or 30 minutes. I’ve lived in places where if I called 911 to report a creepy guy on my property and then hung up and dialed Domino’s to order a pepperoni pizza, there’s a good chance the cops would eat cold pizza while drawing a chalk line around my body.
I need an AR-15 because your effort at obtaining safety by stripping me of my liberty will result in both of us having neither.
I need an AR-15 because I depend upon myself to exercise my natural, civil and Constitutionally protected right to defend my life and preserve my liberty.
I need an AR-15 because, like it or not, we are our own first responders.