There were 36 million hunting licenses sold in the US in 2017. If you figure that there is at least one shooter for each hunter, that comes out to 72 million potential militia members.

Now maybe 10% of these might actually be willing to get actively involved....but that still leaves a 7.2 million man civilian army, each with a family to provide material support. This is a fairly significant number to deal with.

Therevwould be an unknown number of civilians who would want to get involved but have no weapon. These could be easily equipped by the active shooters/hunters each of whom usually owns several different weapons and spare ammo.

Then if you add to that number that probably 50% of the active military would support the civilians either actively or secretly.
Interesting.