tainties about whether this struggle should be governed by the laws of war or by the laws governing law enforcement. Domestic law enforcement authorities in the United States operate on the assumption that lethal force is an option of last resort to protect citizens from imminent harm, whereas military forces engaged in hostilities do not operate with such an assumption. In addition, this struggle is conducted against adversaries for whom national borders are irrelevant; how and to what extent are matters of national sovereignty relevant in such a struggle?
Thus, the post-9/11 security context adds another layer of stress on the traditional nation-state system. In addition, more states are seen as inconsistently willing, or even able, to protect the rights of their citizens, and indeed, may be seen as oppressors of their citizens. As a result, the conduct of such states has increasingly prompted international intervention in the internal affairs of individual nation-states, as in the recent cases of Iraq and Libya. Similarly, states increasingly lack the ability to restrain their citizens if they reach out to attack others, even if the targets of these attacks are nations and even if they may strike with force of existential proportion.
At the highest level of abstraction, the ethics of war and peace can be divided into three major schools of thought—realism, pacifism, and just-war theory. Realists argue that nations, governments, and even individuals resort to war (or armed conflict) when such actions serve their interests, and by extension, that actions taken to serve vital state interests should not be constrained by ethical considerations. Pacifists argue that as a matter of ethics, war and armed conflict are never appropriate. Because neither of these positions are associated with stated U.S. policy, they are not discussed further in this report.
Just-war theory has existed in some form for many centuries. Just-war theorists—the first of whom came from religious and philosophical traditions rather than legal traditions—argue that war or armed conflict can be justified under some circumstances. That is, a state that uses force or violence against another state must have “good” reasons for doing so. The principle is relevant because it assumes that not using force or violence is the normative and preferred state of affairs, and that the use of force or violence is an unusual act that requires some justification. The set of ethical principles regarding justifications for using force or violence is known
20 The discussion of the law of armed conflict and of related material in this section is based largely on Brian Orend, “War,” Stanford Encyclopedia of Philosophy: Fall 2008 Edition, Edward N. Zalta, ed., available at http://plato.stanford.edu/entries/war.