Americans have had a long and varied experience with military government. The names New Mexico, California, New Orleans, Memphis, Cuba, Manila, Mindanao, Samoa, Guam, Vera Cruz, and Coblenz by no means exhaust the list of places where American military or naval governors have exercised control over civil populations. Virtually no effort has been made before the present war to analyze this experience and to draw from it principles to assist in the solution of the problems of the present and immediate future. Military government is of vast importance for the world of tomorrow. It is the transitional phase between the active conflict of armies and the quiet of an established peace. Military government may be—and has been at times in American history—as important for ultimate solutions as major military campaigns.
“Military government,” according to the official definition set forth in the War Department's Field Manual 27–5, “is that form of government which is established and maintained by a belligerent by force of arms over occupied territory of the enemy and over the inhabitants thereof. In this definition, the term territory of the enemy includes not only the territory of an enemy nation but also domestic territory recovered by military occupation from rebels treated as belligerents.” The definition does not cover the whole range of actual occupations in American experience. Military government should not be thought of entirely in terms of enemy territory or enemy populations.