Since 1894, the United States Naval War College had been developing contingency plans for a war with Spain. By 1896, the U.S. Office of Naval Intelligence had prepared a plan that included military operations in Puerto Rican waters. Plans generally centered on attacks on Spanish territories were intended as support operations against Spain's forces in and around Cuba. Recent research suggests that the U.S. did consider Puerto Rico valuable as a naval station, and recognized that it and Cuba generated lucrative crops of sugar – a valuable commercial commodity which the United States lacked, before the development of the sugar beet industry in the United States.