what if half the military and all the gun nuts decide this country is for whites only? the people can fight for tyrrant as well as against it.
You say most people would support a tyrant, which may not be true but let's go with that. Given that, why wouldn't you want the opposition to that tyrrany to have guns? Your take seems defeatist. You want to just try to live peacefully as tyranny spreads?
You really should take a moment to listen to Heller(2008).