The right of self-defense from coercion (including violence) is a fundamental right under libertarianism. In situations of danger to oneself or to one’s property we are entitled to respond with armed or unarmed resistance that may result in killing the attacker. In practice the various legal systems limit such right, namely to situations where defense is not available from the police or military, to prevent the escalation of violence into death.
This restraint is especially important in modern warfare where combatants are expected to avoid collateral damage and to take prisoners rather than kill its enemies. This philosophy of war is contrary to the traditional objective of war which was to kill as many enemies as possible, in some cases to extermination, and where those defeated in a battle expected to be either slaughtered, enslaved or used for ransom.
The modern philosophy of war is the result of various attempts aimed at the regulation of warfare, namely The Hague, Geneva and Genocide Conventions. It resulted in the definition of war crime as a serious violation of such rules, but did not prevent a rise in violence and deaths; partially because of the destructive power of modern weaponry.
Indeed, the new weaponry led to the development of three different types of war – nuclear war, conventional war and guerrilla war. The first has the power to destroy the whole humanity and has so far been avoided through the fear of self-destruction. The second type of war has been progressively substituted by guerrilla-type wars because the development of highly advanced weapons gives its possessor an unmatched superiority in open conflict (illustrated recently in Iraq, Afghanistan and Libya) leading the weaker part to resort to a war of attrition through guerrilla and terrorism warfare.
The rising resort to terrorism, including the use of suicide-bombers, affects all conflicts; whether external (between nations), national (usually separatist) or transnational (often ideological or religious). The way warriors in this type of warfare often switch between the roles of freedom fighters and terrorists means that it is not adequately regulated.
The use of violent tactics to create generalized fear, intimidation or conflicts is not limited to political organizations but it is perpetrated also by criminal organizations. Therefore, the regulation of the self-defense right to prevent the escalation into criminal or warfare violence needs to be comprehensive and consistent.
The pursuit of peace and the preservation of the inviolability of life in a constitutional liberal world require the establishment of both national and international security and judicial bodies capable of simultaneously preserving the rights to self-defense and to life preservation, whether in civil or military conflicts.