When tyranny starts to come in there's a long period where the government can order the police / military to stand down, but doesn't have the power to order the

When tyranny starts to come in there's a long period where the government can order the police / military to stand down, but doesn't have the power to order them to commit atrocities themselves. So there's usually a violent group of government supporters who don't have any special arms or training. eg, Hitler's brown shirts. The second amendment is very affective against them.