[maestro pistolero]

Why do I 'need' an AR-15?

From the Heller decision:

It may be objected that if weapons that are most useful
in military service—M-16 rifles and the like—may be
banned, then the Second Amendment right is completely
detached from the prefatory clause. But as we have said,
the conception of the militia at the time of the Second
Amendment’s ratification was the body of all citizens
capable of military service, who would bring the sorts of
lawful weapons that they possessed at home to militia
duty. It may well be true today that a militia, to be as
effective as militias in the 18th century, would require
sophisticated arms that are highly unusual in society at
large. Indeed, it may be true that no amount of small
arms could be useful against modern-day bombers and
tanks. But the fact that modern developments have limited
the degree of fit between the prefatory clause and the
protected right cannot change our interpretation of the
right.

and there's this:

There are many reasons why the militia was thought to
be “necessary to the security of a free state.” See 3 Story
§1890. First, of course, it is useful in repelling invasions
and suppressing insurrections. Second, it renders large
standing armies unnecessary—an argument that Alexander
Hamilton made in favor of federal control over the
militia. The Federalist No. 29, pp. 226, 227 (B. Wright ed.
1961) (A. Hamilton). Third, when the able-bodied men of
a nation are trained in arms and organized, they are better
able to resist tyranny.

Surely we are not expected to resist tyranny with revolvers.

And finally this:

Undoubtedly some think that the Second Amendment
is outmoded in a society where our standing army is
the pride of our Nation, where well-trained police forces
provide personal security, and where gun violence is a
serious problem. That is perhaps debatable, but what is
not debatable is that it is not the role of this Court to
pronounce the Second Amendment extinct.

Thank you, Justice Scalia