submarine attacks, and a total trade embargo against the Empire of Japan was instituted to deny its military the raw materials its factories and military forces required to continue its offensive actions in China. In late 1941, Japan's Army-dominated government decided to seize by military force the strategic resources of South-East Asia and Indonesia since the Western powers would not give Japan these goods by trade. Planning for this action included surprise attacks on American and British forces in Hong Kong, the Philippines, Malaya, and the U.S. naval base and warships at Pearl Harbor. In response to these attacks, the U.K. and U.S. declared war the next day. Nazi Germany declared war on the U.S. a few days later, along with Fascist Italy; the U.S. found itself fully involved in a second world war. As the United States began to gear up for a major war, information and propaganda efforts were set in motion. Civilians (including children) were encouraged to take part in fat, grease, and scrap metal collection drives. Many factories making non-essential goods retooled for war production. Levels of industrial productivity previously unheard of were attained during the war; multi-thousand-ton convoy ships were routinely built in a month and a half, and tanks poured out of the former automobile factories. Within a few years of the U.S. entry into the Second World War, nearly every man without children fit for service, between 18 and 30, was conscripted into the military "for the duration" of the conflict, and unprecedented numbers of women took up jobs previously held by them. Strict systems of rationing of consumer staples were introduced to redirect productive capacity to war needs. Previously untouched sections of the nation mobilized for the war effort. Academics became technocrats; home-makers became bomb-makers (massive numbers of women worked in industry during the war); union leaders and businessmen became commanders in the massive armies of production. The great scientific communities of the United States were mobilized as never before, and mathematicians, doctors, engineers, and chemists turned their minds to the problems ahead of them. By the war's end, a multitude of advances had been made in medicine, physics, engineering, and the other sciences. This included the efforts of the theoretical physicists working at the Los Alamos National Laboratory on the Manhattan Project, which led to the Trinity nuclear test and thus brought about the Atomic Age. In the war, the United