In July 1937, when the Second Sino-Japanese war began, Puyi issued a declaration of support for Japan. In August 1937, Kishi wrote up a decree for Puyi to sign calling for the use of slave labour to be conscripted both in Manchukuo and in northern China, stating that in these "times of emergency" (i.e. war with China), industry needed to grow at all costs, and slavery was necessary to save money. Driscoll wrote that just as African slaves were taken to the New World on the "Middle Passage", it would be right to speak of the "Manchurian Passage" as vast numbers of Chinese peasants were rounded up to be slaves in Manchukuo's factories and mines. From 1938 until the end of the war, every year about a million Chinese were taken from the Manchukuo countryside and northern China to be slaves in Manchukuo's factories and mines.