U.S. forces Japan to open its country to outside trade after showing off the U.S. military power. This begins a power struggle for control of the Pacific Ocean for both nations.
"REMEMBER THE MAINE" was a "attack" on the U.S.S. Maine in Havana Harbor. This event was intensified by the use of Yellow Journalism, in which reporters sensationalized this story. In the end, the attack led to the beginning of the Spanish-American War
One major cause of Imperialism is the spread of Religion and culture. Citizens of the United States would travel to these nations to spread Christianity. The above image shows the attempted spread of Christianity to the Hawaiian Islands.