The end of World War I brought many changes to Europe, Russia, and the United States. The years of war had been hard on many countries. Because of severe famine, Russia had signed a peace treaty and withdrawn from the war earlier than other countries. The Russian Revolution and the assassinations of the Romanovs did little to improve life for its citizens. Life was not much better in post-war Europe or America. The Spanish flu of 1918 left more than twenty million dead, and the war had been responsible for another eight and a half million deaths. The war had inflicted more than one hundred billion dollars worth of damage, and many countries were in serious debt. A year after the war ended a scientist finally succeeded in splitting an atom, opening the way for greater, more dangerous discoveries. Technology was allowing faster automobiles, new highways, and...