In 1800, armed citizens may have made a difference. Armed citizens are of little help in repelling an invading army. Southerners were armed in the civil war, they did nothing to stop the invading Yankees
As it is, the US is isolated by two oceans and is not vulnerable to an invasion.
The southern states did "nothing" Do you know how many casualties the Union Army suffered? They did alot more than nothing.
We disagree here, no country is or will ever be impenetrable.
We are talking about armed civilians and their effectiveness in fighting off an invading force
It is a Red Dawn/NRA fantasy that armed civilians are a last line of defense that an invading force is afraid of. The second amendment envisioned armed civilians necessary to form the nations defense. It never worked
In the War of 1812 we had second amendment armed civilians who did nothing to prevent the regular British Army from marching in and burning our capital
In the Civil War, the South had an armed civilian population that did nothing to prevent the Yankees from marching in, taking their food and destroying their crops
These are civilians who had muskets and rifles that were similar to what the invading armies had. Fighting a modern Army would be futile