Question

What speech set the nationalist policy of the U.S. five years after the War of 1812?

Answer 1

The Monroe Doctrine.

Answer 2

President James Monroe's speech which later came to be known as The Monroe Doctrine set the nationalist policy of the U.S. five years after the civil War of 1812.

This doctrine of the James Munro (The President of the United States) opposed the European colonialism in the Americas beginning in 1823.