As a young British officer in the Gurkha regiment, John Mackinlay served in the rainforests of North Borneo and experienced firsthand the Maoist-style insurgencies of the 1960s. Years later, as a United Nations researcher, he witnessed the chaotic deployment of international forces to Africa, the Balkans, and South Asia, and the transformation of territorial, labor-intensive uprisings into the international insurgent networks we know today. After...