To the extent that individuals like that rebel, they are simply setting themselves up for extermination. This is not the 1860s with a distributed state-controlled military; the rebels will not have the supply chain for modern warfare. They will at best be a dispersed nuisance that can cause pain, but to the extent they do so they ensure their own destruction.

If someone talks up rebellion and civil war to try to prevent some legal action of a democratically elected government, I will just look in them in the eye and say "Rebel and be damned."