The existence of full-time professional soldiers and police employed by the state is a fairly new phenomenon. Their role as a distorting influence on the economy ("the military-industrial complex") has been well-researched. Their ineffectiveness as an defensive force compared to democratic, voluntary and well-regulated militia is also noted. Ultimately armies are only effective at invading other countries, and police as a tool for tyrants to "invade" the unarmed local civilians. As James Madison accurately wrote: "War is the parent of armies; from these proceed debts and taxes; and armies, and debts, and taxes are the known instruments for bringing the many under the domination of the few." We support contributions to international security and universal rights, whilst opposing all nationalist wars.
Supporters of the state monopoly on violence suggest individuals and groups will inevitably use violence. The appropriate organisational model for a classless, stateless, but organised society is the militia, the armed citizenry, a trained, voluntary and well-regulated democratic and federal force that carries out emergency services and protection. Such organisations have shown on successive times in history that their capacity, local knowledge and morale in resistance and defense is exceptional; but their ability to wage an aggressive war is hopeless - this is a virtue.
Examples:
José Figueres Ferrer of Costa Rica who, as the head of military junta after a dispute election, gave blacks citizenship, women the vote, re-established a democratic constitution, abolished military rule and abolished the military. Not surprisingly, Costa Rica has been one Latin American country that has not suffered any other military coups.
Switzerland, through a civilian militia system, avoided invasion when standing armies failed (See: Stephen Halbook, "Swiss and the Nazis: How the Alpine Republic Survived in the Shadow of the Third Reich", 2006).
The essay by Robert Higgs, "The Living Reality of Military-Economic Fascism" (http://mises.org/story/2450), published on the von Mises Institute website last year which explores how "military interests" distort democratic processes through contracts and donations.