Yes and No. Would many small militias "win". Of course not. Would they cause nearly endless pain and chaos for decades? Most certainly. Some of them would

Yes and No. Would many small militias "win". Of course not. Would they cause nearly endless pain and chaos for decades? Most certainly. Some of them would also be members of the standing military and embedded in every level of government. Even the most malevolent narcissistic sociopath dictators don't want such a high maintenance and unstable situation.