Thousands of Americans flocked to downtown D.C. in "Make America Great Again" hats and patriotic gear displaying Old Glory despite the balmy weather and thunderstorms brewing.

The Spanish-American War was the first major international conflict for a reunited nation since the Civil War. It ended in a U.S. victory that established an American empire: Spain ceded Cuba, Puerto Rico, and Guam, and the U.S. purchased the Philippines for $20 million. Puerto Rico and Guam remain U.S. territories.