WASP (from left) Frances Green, Margaret Kirchner, Ann Waldner and Blanche Osborn leave their B-17, called Pistol Packin' Mama, during ferry training at Lockbourne Army Air Force base in Ohio. They're carrying their parachutes. National Archives hide caption

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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. Marko Drobnjakovic/AP hide caption

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A member of the Kurdish internal security forces (known as the Asayish) inspects the Alaya prison in the northeastern Syrian city of Qamishli on April 22. Delil Souleiman/AFP/Getty Images hide caption

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Federal securities regulators have filed civil fraud charges against Texas Attorney General Ken Paxton over recruiting investors to a high-tech startup while he was a member of the state House of Representatives. Eric Gay/AP hide caption

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A box of Lumigan eye-drops, produced by Allergan Plc, stands next to a box of Viagra tablets, produced by Pfizer Inc. The Irish and American drugmakers were planning to merge, but the deal has been called off after a change in U.S. tax law reduced the potential benefits. Bloomberg via Getty Images hide caption

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Attorney General Loretta Lynch and FBI Director James Comey stand by a poster showing Iranians who are wanted by the FBI for computer hacking during a news conference at the Justice Department in Washington on Thursday. Jacquelyn Martin/AP hide caption

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President Obama and Canadian Prime Minister Justin Trudeau walk from the Oval Office to a joint press conference in the Rose Garden of the White House on Thursday. Chip Somodevilla/Getty Images hide caption

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