They can have all the advanced weaponry that they want.

Those who run all that advanced weaponry are still going to have friends and family in the general population. They might have some semblance of a conscious and many won't want to fire on American citizens. (This is the true reasons to bring homosexuals into the military, they don't care if some breeders die.)

They will also want to go home at some point. (Think about it.)

This is a very large country, do you really think that TPTB will be able to control the entire country when we couldn't stop the uprising in Afganistan and Iraq, even those we've been there for a decade?