Guns are a tradition, a very central part of our culture and symbol of our freedom. We hunt with them, collect them and shoot at all kinds of targets. Our Founding Fathers considered it a duty for citizens to not only possess guns but to also be ready to protect themselves from enemies external and internal. That explicitly means a rebellion against a government out of control.
Currently in the US there are 21.8 million million veterans. All are sworn to uphold and protect the Constitution. A huge percentage of those are committed and willing to do just that if necessary. There is your militia. I would bet they are very nearly all well armed.
I have no idea if regular forces would respond if ordered to attack their former brothers in arms. Some would. Our militia could not stand against the active military in face to face battle but that is just not how things work any more. ..
“Let my armies be the rocks and the trees and the birds in the sky.” Charlemagne
Ho Chi Mihn studied three Americans while in Paris: Francis Marion, known as the Swamp Fox. John Mosby, known as the Grey Ghost. Ethan Allen’s Green Mountain Boys. All had a hand in developing non-traditional warfare. Ho used our own tactics against us knowing his army could not stand against the might of conventional warfare.
As for military expedition goals it would simply be the collaps of the Federal government. A large scale insurrection would quickly acheive a general collapse of our economy which is already sitting on a two-legged stool.
Protecting our liberties and freedom is not a far-fetched idea except in the minds of those in the well-insulated stronghold of Washington, DC. Even so, there are now more guns owned by private citizens than there are citizens. The amount of ammo flying off the shelves across the country is astounding.
“You cannot invade the mainland United States. There would be a rifle behind every blade of grass.” Isoroku Yamamoto
Outside the US few noticed a standoff resulting from Federal action against a Nevada rancher, Cliven Bundy. A large group of “well-armed militia” gathered to protect Bundy from heavily armed Federal agents. This standoff had a convoluted background but ended with citizens facing-down the government. The Federals backed-down this time.
Most in this country now consider the government and anything associated with it as “them”. When a free nation devolves to “us” vs “them”, then gun rights become very important.