re: World's largest private army,U.S. hunters.

Coming to this one late but yeah, all the maneuvering in the world won't help you if there's nobody to outflank. I mean unless they're willing to go genocidal on entire sectors but that still wouldn't help them long.

Logistic support for the invaders would be damn near impossible. Interstate or not. There would probably only be large 'battlefields' occur between the army and the invaders. Army including all armed forces including and especially National Guard. But every other waking moment they were here would be under threat of some body like one of us taking a very well placed shot at them and killing someone every day while they can only react from bases.

Would you want to leave a firebase and patrol Louisiana? HELLLLLLL NO.