There are roughly 100 million firearms owners in the US.
If 99% of them obey an order to “Turn ‘em in”, that leaves a million holdouts.
If 90% of those go out in a “blaze of glory” in the first week, that still leaves 100,000 survivors.
And those 100,000 will also be the most capable and motivated resisters. Northern Ireland was kept in turmoil for several decades by a few hundred guys. The DC/Maryland/Virginia area was kept in turmoil for several weeks by TWO guys.
If the first 10,000 of the resisters each takes one “occupier” with him when he dies, how enthusiastic do you think the “occupation” will be?
And that math is very conservative, IMHO.