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Iranian schoolgirls wave their national flag and hold an anti-US slogan during celebrations in Tehran's Azadi Square (Freedom Square) to mark the 37th anniversary of the Islamic revolution on February 11, 2016. (ATTA KENARE/AFP/Getty Images)

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The Baker test during Operation Crossroads, a series of two nuclear weapons tests conducted by the United States at Bikini Atoll, July 25, 1946. (Galerie Bilderwelt/Getty Images)