Individuals with guns defending against a modern military with drones and tanks is a fantasy.
Or a bunch of dudes in the deserts of yemen couldn't defend against a modern military with aircraft carriers, realtime control of almost all communications, autonomous drones and missiles and 5th gen fighters
History and current events seem to be disagreeing with you.
Suppression of populace is vastly different than "trying to beat terrorism" or end resistance in a jungle.
Go take a look at actutal comparable environments, like china, or north korea for how well that goes for the dissenters