Years of democratic fear mongering has affected the view that many of the people this affects so they don't have firearms. Some have firearms but don't carry, they leave it at the house.
The people that were armed in case of government tyranny are fine with this. It's almost like a lot of them were armed because there wanted this to happen to the opposing political party but were scared someone would get to them first.
I assumed they were sending them to APO addresses and that's how the military knew.