Demon coreThe demon core was a spherical subcritical mass of plutonium in diameter, manufactured during World War II by the United States nuclear weapon development effort, the Manhattan Project, as a fissile core for an early atomic bomb. The core was prepared for shipment as part of the third nuclear weapon to be used in Japan, but when Japan surrendered, the core was retained at Los Alamos for testing and potential later use. It was involved in two criticality accidents at the Los Alamos Laboratory on August 21, 1945, and May 21, 1946, each resulting in a fatality.
Government of Meiji JapanThe Government of Meiji Japan was the government that was formed by politicians of the Satsuma Domain and Chōshū Domain in the 1860s. The Meiji government was the early government of the Empire of Japan. Politicians of the Meiji government were known as the Meiji oligarchy, who overthrew the Tokugawa shogunate. After the Meiji Restoration, the leaders of the samurai who overthrew the Tokugawa shogunate had no clear agenda or pre-developed plan on how to run Japan.
Shin'yō-class suicide motorboatThe Shinyo were Japanese suicide motorboats developed during World War II. They were part of the wider Japanese Special Attack Units program. Towards the end of 1943, in response to unfavorable progress in the war, the Japanese high command heard suggestions for various suicide craft. These suggestions were initially rejected as "defeatist" but later deemed necessary. For the naval department this meant kamikaze planes, kaiten submarines, fukuryu suicide divers or human mines, and shinyo suicide boats.
KantokuenKantokuen (関特演, from 関東軍特種演習, Kantōgun Tokushu Enshū, "Kwantung Army Special Maneuvers") was an operational plan created by the General Staff of the Imperial Japanese Army for an invasion and occupation of the Russian Far East, capitalizing on the outbreak of the Soviet-German War in June 1941. Involving seven Japanese armies and a major portion of the empire's naval and air forces, it would have been the largest combined arms operation in Japanese history up to that point, and one of the largest of all time.
Japanese diasporaThe Japanese diaspora and its individual members, known as Nikkei (日系) or as Nikkeijin (日系人), comprise the Japanese emigrants from Japan (and their descendants) residing in a country outside Japan. Emigration from Japan was recorded as early as the 15th century to the Philippines, but did not become a mass phenomenon until the Meiji period (1868–1912), when Japanese emigrated to the Philippines and to the Americas.