When the second amendment was penned, people owned flintlocks.

[Straw Man]

124. Justifiable paranoia.

That amendment should have been repealed as soon as the citizen militia idea was abandoned.

It has yet to be abandoned, at least on paper.

(a) The militia of the United States consists of all able-bodied males at least 17 years of age and, except as provided in section 313 of title 32, under 45 years of age who are, or who have made a declaration of intention to become, citizens of the United States and of female citizens of the United States who are members of the National Guard.

(b) The classes of the militia are—
(1) the organized militia, which consists of the National Guard and the Naval Militia; and
(2) the unorganized militia, which consists of the members of the militia who are not members of the National Guard or the Naval Militia.

--https://www.law.cornell.edu/uscode/text/10/311

The further we get away from a citizen army, the less democratic our republic is. The end of the draft ushered in the age of the all-volunteer army that doesn't accurately represent the populace as a whole. This is both unjust and dangerous. It is unjust in that it allows the wealthier segments of society to duck out of the duty of defending their interests (or the nation's interests, if we're being generous). It is dangerous in that it establishes a "warrior class" that sees itself as separate from the society at large and not answerable to them.

I'm not saying we don't need a standing army. However, I think the European model of mandatory national service, with the addition of heavier reliance on a civilian militia, would be a lot healthier for our society than what we have now.