Collective defense is the ideal organization of a defense system in a communal, anarchist society. It involves a militia system, quite similar to that already practiced in Switzerland. With collective defense, every individual in a community may own a weapon or firearm of some kind, so that no single individual can wield power over a community by might or size of arsenal. Every individual has the freedom to defend himself or herself, without being able to oppress anyone else.

This system of defense is superior to that of a standing army because allows the individual to live without fear of military oppression. this military oppression is the only purpose for which a conventional military can exist. It also allows an individual or a community to eliminate anyone who might try to oppress them by economic means. The collectively secure community can deal with such transgressors in much the same way as a living organism neutralizes offending bacteria. There is no regulation of the collective militia, since in that envisioned society no central authority exists. However, the militia can act to ensure that individuals co-operate freely with one another out of necessity.