In 1898, the United States went to war with Spain. By the end of the war, the United States had acquired the overseas territories of Puerto Rico, the
Philippines, and Guam.
This is an example of which theme in American history?
A. Reinvention
B. Imperialism
C. The expansion of civil rights
a
D. Progressivism

I would say B.Imperialism

Explanation:

Treaty of Paris

The war ended with the 1898 Treaty of Paris, negotiated on terms favorable to the U.S. It ceded ownership of Puerto Rico, Guam, and the Philippine islands from Spain to the U.S. and granted the U.S. temporary control of Cuba.

How did the US end up with an empire after the Spanish-American War?

In France, the Treaty of Paris is signed, formally ending the Spanish-American War and granting the United States its first overseas empire. The Spanish-American War had its origins in the rebellion against Spanish rule that began in Cuba in 1895.

B. Imperialism

Explanation:

Hope it helps!

they believed democracy was worth the fight