I like to think that police and military personnel have family and friends they care about too, and aren't soulless robots ready to gun down their fellow men and women who they took vows to serve when they joined the force at the command of a suit in Washington. Think, if you were them, what kind of world would you like you, your family, and friends to live in? I find that enough of them would make the right decision that if the PEOPLE fought back, they would have a winning chance. Think about the rest of the world too. Is Russia going to sit back and do nothing, when they could be funding/supporting those rebels against the U.S. government instead? AND they can do it from the moral high ground too, since they're helping the oppressed rebels against a totalitarian government. Extra power.

The U.S. was founded on rebellion. And I believe enough Americans would readily backstab an illegitimate U.S. government (one that has stopped serving its people and instead serves itself) in pursuit of good.