And all are useless. These militias and the regular army are just a prison camp without walls. Their mission is to not overthrow the government. Military effectiveness is not a factor.
The militias are set up to defend against attacks from the rear, coasts, and from airborne / airmobile attacks. North Korea had a lot of trouble in being outflanked and cut off in the Korean War, so Kim Il Sung made the idea of an 'impregnable rear' one of his twelve guiding military principles.
That having been said, their militia would be little more than cheap, ineffective cannon fodder. They'd be of marginal use in defending NK from an attack, and no use in supporting an advance south. I was just pointing out to another poster that the populace is by no means disarmed.