Inca built stone-paved roads over mountains which are called Inca Roads.
It did not lead to the Civil War, what led to the civil war was the war of 1812. That was when U.S.A recognized that it needed to become stronger, and slaves were transported to the United States and put in the working class under bad conditions. Child labor and prejudice began there as well.
Answer:
The Hartford Convention
Explanation:
"This mostly Federalist convention in New England ended up suggesting some constitutional amendments but was alleged to consider the secession of New England from the Union and a separate peace with Britain. After the war the convention was widely viewed as an act of treason and a black mark on the reputation of the Federalist party."
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