This book lists hundreds of instances in which the United States has used its armed forces abroad in situations of military conflict or potential conflict or for other than normal peacetime purposes. It is intended primarily to provide a rough survey of past US military ventures abroad, without reference to the magnitude of the given instance noted. The listing often contains references, especially from 1980 forward, to continuing military deployments especially US military participation in multinational operations associated with NATO or the United Nations. Most of these post-1980 instances are summaries based on Presidential reports to Congress related to the War Powers Resolution. The instances differ greatly in number of forces, purpose, extent of hostilities, and legal authorisation. Eleven times in its history the US has formally declared war against foreign nations. These eleven US war declarations encompassed five separate wars: the war with Great Britain declared in 1812, the war with Mexico declared in 1846, the War with Spain declared in 1898, the First World War, during which the US declared war with Germany and with Austria-Hungary during 1917, World War II, during which the US declared war against Japan, Germany, and Italy in 1941, and against Bulgaria, Hungary, and Rumania in 1942.