Sure, but look at the recent protests. Armed men protesting state level governments openly egged on by the whitehouse and organized by rich political dark money.

Armed men with guns were militarily consequential during the Civil War. Today, they are a danger only to civilians.

Small arms and asymmetrical tactics have quite substantive results in places like Afghanistan, Yemen, and Iraq. Let's not write off potential danger because of lopsided resourcing.

There was a distinct period before the armed attack of hostilities between the federal government and the southern states, e.g. Nullification crisis and the “tariff of abominations”.

I’m not sure it particularly matters which side started it, you still had basically open violent conflict between democrats and republicans for decades, before and after the war.

One side was fundamentally built upon slavery (and for the "but but but" kid in the back you will notice that the Union did not exempt their slave states from the Thirteenth Amendment) and attacked the other out of fear that their slaves would be taken away.

I dunno, that feels like that kinda matters, too.