Chapter 6 examines the creation of the positive laws of war in the late 19th and early 20th centuries, focusing specifically on the diplomatic negotiations that led to the 1899 and 1907 Hague Conventions and the 1923 Hague Draft Rules on Air Warfare. It shows how emotional framing shaped the creation of the idea of lawful military targets in international law. Further, it examines the permissive effects of the laws of war by examining how norms regarding lawful military targets shaped Allied bombing policies in the European theatre of World War II. Although anti-civilian targeting norms were certainly violated many times during World War II strategic bombing, this chapter shows that these norms did have an effect in some situations. Further, they shaped how the Allies justified their policies to the public.