In the end, effectiveness is irrelevant. Basic human dignity requires that you always have the option to resist.

> Where's the evidence that an armed population can resist tyranny, however you define it?

Drug gangs in latin america.

In my country, drug traffickers have become so organized they have established control over a quarter of Brazil's continental territory. They have armies, laws, tribunals, even taxes. They have essentially pulled off a stealthy unannounced secession. It's theorized that they control politicians, judges.

All thanks to the fact they were willing to arm themselves and die in order to achieve their own ends. The rest of the brazilians constantly prove unwilling to do either, and as a result they are dominated by the people with guns. Police state, military dictatorship, drug gangs, makes no difference.