During the Civil War, which region of the United States supported the expansion of States' Rights?

The South.

Explanation:

The concept of states rights is not found in the constitution. That's because States don't have rights. People have rights. States have powers that the people grant to them. Powers and Rights are two different things. The Constitution says We the People, not We the States. People have inalianable rights. They have rights that come to them from birth. There is no right to print money, or to levy a tax. Those are powers that are authorized by the people and granted to the states. A police officer has no right to issue a ticket to you for speeding. You have the same rights he has. No more, no less. He has the authority granted by the people to give you a speeding ticket. Rights and powers are two different things.

i would think it's industries and hydroelectric power

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