Answer:
Imperialism means to incite power by using diplomacy or military force. This was seen in The Spanish American War where the US fought Spain and ended gaining Puerto Rico, Guam and The Philippines.
Explanation:
It doesn't have a definition it's a phrase president Thomas Jefferson used in his first inaugural address in 1801 calling for a cautious, isolationist foreign policy
There are a few nicknames for him, but I believe the one you want is: The Great Communicator.