The just war tradition is an evolving discourse on how individual soldiers and their commanders may make war ethically or how they can pursue [Page 930]their nation’s interests with armed force while retaining their essential humanity. Rooted in the work of Roman jurists as elaborated by medieval Christian theologians, most prominently Saints Augustine and Thomas Aquinas, its precepts were gradually accepted by 18th- and 19th-century soldiers as elements of the “customary usages of war.” Later, in a more systematic process, the “tests” of the just war tradition became structural elements of international law via the Hague Conventions of 1899 and 1907 and the Geneva Conventions of 1864, 1906, 1929, and 1949.

The morality of a nation’s resort to war and its ethical conduct of war can ...