U.S. Navy air wing captains pause on the flight deck of the aircraft carrier USS Theodore Roosevelt last September. Every day, the steam-powered catapult aboard this massive ship flings American fighter jets into the sky, on missions to target the extremist Islamic State group in Iraq and Syria.
U.S. soldiers stand at a checkpoint around Lakokhel camp in Afghanistan in 2010. Many soldiers return from war suffering from "moral injuries," or dealing with the fact that their sense of right and wrong was violated.
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Classrooms across Gaza are crowded with as many as 50 or 60 students, principals say, as dozens of school buildings have been destroyed or damaged, or are still housing people who lost their homes.