if the 20th century has shown us anything, its that militia who lack drilling, heavy weapons (81mm mortars, 105mm guns), anti-tank and anti-air capacity get rolled. (Krondstat and Tambov; Spain '36; Bosnia 90s). Whereas militia with even the most rudimentary capacities in this regard can put up an excellent showing. (Hungary '56 held off the Soviets for 2 weeks, and mauled them).
Thus there's no correlation between "rights to bear small arms" and the ability to engage in successful anti-state warfare.