I'm just not buying it. Even with their massively over-inflated budget and their guilt-elimination drones there is no way the DoD could maintain an armed occupation of America. They are having a hell of a time doing it in a country less than one-tenth the size with less than one-tenth the people, filled with people who have been thoroughly dehumanized by popular media, people with far fewer connections to the outside world, and people for whom the soldiers have no tribal connections.
Thinking they would do better occupying America than Afghanistan is a really strange form of patriotic hubris.
(Lest you get the wrong impression, I support gun control and think that worrying about the possibility of Americans having to fight the American army is incredibly silly.)