Mary McHugh mourns her slain fiance Sgt. James Regan at “Section 60” of the Arlington National Cemetery May 27, 2007. Regan, a US Army Ranger, was killed by an IED explosion in Iraq. (Photo by John Moore/Getty Images)

View of a Spitfire from the cockpit of an He111,somewhere over Southern England 1941 – 2014. (Photo by Adam Surrey)

Two women cry in grief after armed assailants in a motorcycle shot their loved one in a main thoroughfare on July 23, 2016 in Manila, Philippines. The victim was an alleged drug peddler a claim disputed by his wife and maintained her husband is nothing more than a pedicab driver plying his trade when he was shot in front of her. Philippine President Rodrigo Duterte declared a war on crime and drugs after winning the presidential elections on May 9, 2016. President Duterte has recently been living up to his nickname, “The Punisher”, as Philippine police have been conducting night time drug raids on almost a daily basis. (Photo by Dondi Tawatao/Getty Images)

Brush fires in Everglades National Park, Florida make for a dramatic Milky Way in this panorama. A photographer set out to inspire awe in nature's wonders through the tropical wetlands of Florida. (Photo by Mark Andrew Thomas/Rex Feature/Shutterstock)

Activists stage a theatrical play where gay people are restrained by others wearing masks depicting Russian President Vladimir Putin, during a protest against Russia's new law on gays, in central London, Saturday, August 10, 2013. Hundreds of protesters, called for the Winter 2014 Olympic Games to be taken away from Sochi, Russia, because of a new Russian law that bans “propaganda of nontraditional sexual relations” and imposes fines on those holding gay pride rallies. (Photo by Lefteris Pitarakis/AP Photo)

Kazuo Hirai, President and Group CEO of Sony Computer Entertainment America, presents the Playstation Vita at the Sony Playstation media briefing on the eve of the Electronic Entertainment Expo (E3) on June 6, 2011 in Los Angeles, California. More than 45,000 people are expected to attend the annual three-day convention to see the latest games and announcements from the gaming industry. (Photo by David McNew/Getty Images)

Period-costumed actors participate in the 150th anniversary re-enactment of the surrender of General Robert E. Lee to General Ulysses S. Grant at the Museum of Confederacy in Appomattox, Virginia, April 9, 2015. (Photo by Jay Paul/Reuters)

Battle-weary American troops withdraw from Yong San in Korea. (Photo by Keystone/Getty Images). 1950