Many nations had already abolished slavery.
Let me know if you want to know why.
During 1931-1945(world war 2) japan became to build up and later went to war with the united states (August 1941 The Battle of Pearl Harbor)
hope this help
It is false that Communism was the dominant economic force of the twentieth century, although it certainly overtook a great deal of territory. Capitalism was still overall dominant.
