WW1 - ⑤ Part Five : The Final • 23 Feb 2025 World War I - The Fifth Story : The Final Chapter The United States in the Early 20th Century <RMS Lusitania arriving in New York City in 1907> On May 7, 1915, the British passenger liner RMS L… 1917 U.S. declaration of war on Germany1918 ArmisticeAllies vs Central PowersEconomic impact of WWILusitania sinkingRealism in international politicsU.S. entry into WWIWWI casualties