B. It was a challenge to decide how to divide forces and protect two coasts.
Answer:
The history of civil rights in the twentieth-century United States is inseparable from the history of the Great Migration. From the end of World War I through the 1970s, extraordinary numbers of African Americans chose to leave the South with its pervasive system of legalized racism and move to cities in the North and West. While we often associate the Great Migration with the decades around the two World Wars, historians have recently established that many more people moved away from the South after 1940 than before. Between 1940 and 1980, five million African Americans moved to the urban North and West, more than twice the number associated with the first wave of migration from 1915 to 1940.
Explanation:
Hope this helps.
It would be important because the ways we are using now are not very affective
