The correct answer is true!
Between the political chaos and multiple civil wars within the empire, it came as a surprise when Morocco invaded Songhai unexpectedly. The main reason for the Moroccan invasion of Songhai was to seize control of and revive the trans-Saharan trade in salt and gold.
It is very much hard to answer.
It was mainly because of how the North and the South of America had different lifestyles and economy's. You would be surprised to know that the Democratic party back then supported Slavery and the republicans dint support Slavery.
Plain Answer: Because of Slavery, Way of Life and Different Economy. The Democratic Party would do anything to keep themselves supported.