Answer:
The US was interested in events occurring in Puerto Rico because they needed Puerto Rico. In order to preserve their area in the Caribbean and protect the coming Panama Canal, they needed Puerto Rico.
Step-by-step explanation:
On April 21, 1898, the United States declared war against Spain. ... The reasons for war were many, but there were two immediate ones: America's support the ongoing struggle by Cubans and Filipinos against Spanish rule, and the mysterious explosion of the battleship U.S.S. Maine in Havana Harbor.