World War II: The global conflict that took place between 1939-1945 involving many of the world's nations divided into two opposing military alliances: Allies vs Axis powers.
Isolationism: A policy or doctrine advocating keeping one's country's affairs separate from those of other nations by declining to enter into alliances or international economic commitments.
Hiroshima & Nagasaki: Two Japanese cities on which the U.S dropped atomic bombs in August 1945 leading to Japan’s unconditional surrender in World War II.