Economic growth depended upon the continued expansion of the empire.
The developed a bomb, not just that, the Nazis wanted to take over more land and that meant they where a threat to America, the Soviets teamed up with the US to create a bomb and it turns out the Nazis weren't even going to bomb them
For human cost we lose soldiers which can sisters, brothers, fathers, mothers, for economic it puts big debt because people lose jobs and lose money, and for political it can be a positive or negative output.
Which results in waves in the ocean.
