2nd Amendment

Three things about our Constitution I do not understand:
1) The arguments that the 2nd Amendment is meant personally rather than collectively, given that it starts with that "well-regulated militia" clause (which individuals, by definition, cannot be)
2) Why the Five aren't considered "activist" when they've consistently overwritten decades of precedent;
3) How in the world you can call yourself a "strict" constitutionalist, given #2.

I mean this honestly: I do not understand it at all.