Answer:
It comes from the remark Roosevelt made after losing the presidency, saying he felt "as strong as a bull moose"
<span>Japanese militarists hoped to build an empire to rival western colonial empires.--Manchuria was rich in iron ore needed to become an industrial power.
Japan hoped to become a 'western' power by gaining an empire. Manchuria was a good choice because of the resources available to Japan for industry. These resources would allow for more modern transportation and the creation of a steel industry.
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Hiroshima was first, Nagasaki was second
hope this helped :)
