Beyond abolishing slavery in the United States, the Civil War was a pivotal event in American history because it

Responses
A was a direct cause of the Spanish-American war in 1898.was a direct cause of the Spanish-American war in 1898.
B established a military alliance between America and Great Britain.established a military alliance between America and Great Britain.
C established the supremacy of the national government over state governments.established the supremacy of the national government over state governments.
D allowed the United States to spread its borders westward to the Mississippi River.

C established the supremacy of the national government over state governments.