Well-regulated just means well trained.  Any farmer or trapper in the Revolutionary era, would need "training" in standardized military tactics after applying to fight with the Continental (pre- USA) Army. I say "pre" because we hadn't actually won the war and started enjoying citizen's rights.  "Training" consisted in drilling said farmers and trappers in marching, troop maneuvers and other military tactics current at the time. Set-piece battles and don't shoot officers, kind of thing.  It is silly to think people in a free, or soon to be free country were not armed with the best and most lethal arms available. I suspect liberals get "well-regulated" confused because they enjoy and desire greater "regulation".