South Vietnamese forces escort suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street February 1, 1968, early in the Tet Offensive. Moments later, Lem was executed by Gen. Nguyen Ngoc Loan, chief of the national police. (Photo by Eddie Adams/AP Photo)

A worker walks beside the ocean liner Queen Mary II in a dock at Blohm&Voss shipyard in Hamburg, Germany, June 14, 2016. The mighty Queen Mary 2 is just days away from setting sail after the most expensive refurbishment of any ship in history. Tens of millions of pounds have been spent on the 151,200-tonne ship as 2,500 workers complete the month-long major interior overhaul. (Photo by Fabian Bimmer/Reuters)

A glasses-free Toshiba 55-inch 3-D 4x full HD TV shows the movie, “Coraline” at the 2012 International Consumer Electronics Show at the Las Vegas Convention Center January 11, 2012 in Las Vegas, Nevada. The TVs are scheduled to be available this year and will come with embedded cameras with facial recognition capability so depending on where you are sitting, the set will adjust the viewing point for the best 3-D experience. (Photo by Ethan Miller/Getty Images)

American soldiers leaping from an armoured personnel carrier during exercises in Korea, 17th March 1954. (Photo by Three Lions)

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)

These stunning color portraits, produced by the U.S. Office of War Information during World War II depict the role of women in the US war effort. All of the images were shot on 4x5 color transparency film by Howard R. Hollem and Alfred T. Palmer during 1942 and 1943 and were turned over to the Library of Congress Prints and Photographs Division in 1944. They are seen here with their original captions.

Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

A portrait of French WWI soldier Edouard Marius Ivaldi is displayed on a tablet, in this illustration picture, alongside his battlefield grave memorial, a wooden cross with a battlefield helmet in Champagne, eastern France, November 3, 2015. (Photo by Charles Platiau/Reuters)