Was the atomic bomb necessary at the end of the war explain why

Kansas Nebraska act was proposed by two main leaders Lincoln and Douglas who were supporting pro slavery and Anti-slavery each.  

Explanation:

Kansa-Nebraska act was drafted in order to encourage a trans railroad project and it stipulated that Nebraska territory need to be defined and he repealed the sacred and compact Missouri compromise which had already declared the territory limit based on the latitude.

Douglas desired to build two territories Kansas and Nebraska, but the whether these territories prefer to be slave or frees state depends upon the settlers movement and migration. Southern states were in approval of slavery but northern states were divergent about it.

By the time Kansas was announced to be a state with the border limits decided, many southern states began to withdraw from the Union and there was a great internal war between the anti and pro slavery groups which finally made Kansas to get the name ‘bleeding Kansas.’