| •1880–1900 | U.S. creates third most powerful navy |
| •1893 | U.S. plantation owners overthrow Queen Liliuokalani of Hawaii |
| •1895–1898 | Cuban War for Independence |
| •1898 | U.S. battleship Maine explodes |
| The War of 1898 |
| Anti-Imperialist League founded |
| •1899–1902 | Philippine-American War |
| •1901 | Platt Amendment passed |
| •1904 | Roosevelt Corollary announced |
| •1909 | U.S. intervenes in Nicaragua on behalf of U.S. fruit and mining companies |
| •1914 | Panama Canal opens |
| World War I begins |
| •1915 | German submarine sinks the Lusitania |
| •1916 | Wilson sends U.S. troops into Mexico to capture Pancho Villa |
| •1917 | Zimmermann telegram |
| United States enters World War I |
| Espionage Act |
| War Industries Board established |
| Committee on Public Information established |
| •1918 | Sedition Act |
| National War Labor Board established |
| Germany surrenders, ending World War I |
| •1919 | Wilson loses battle for ratification of Treaty of Versailles |