A weeping South Vietnamese mother and her three children are shown on the deck of this amphibious command ship being plucked out of Saigon by U.S. Marine helicopters in Vietnam, April 29, 1975. (Photo by AP Photo)

Men ride a motorcycle in front of destroyed houses after Hurricane Matthew passes Jeremie, Haiti, October 7, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

New York Sports Club Gets In The Election Spirit With Hillary Clinton And Donald Trump Boxing Inspired Class on October 27, 2016 in New York City. (Photo by Thos Robinson/Getty Images for DKC for New York Sports Clubs)

A wheelbarrow loaded with two butchered pigs is seen at La Saline slaughterhouse in Port-au-Prince, Haiti, March 19, 2015. Reuters photographer Andres Martinez Casares: “The grunts of a pig or the bleating of a goat are one thing. Then there's the sound of animals about to be killed. That's something else. If you haven't heard that before, it's quite something... (Photo by Andres Martinez Casares/Reuters)

A girl watches an acrobatic performance at the Longtan park as the Chinese Lunar New Year, which welcomes the Year of the Monkey, is celebrated in Beijing, China February 9, 2016. (Photo by Damir Sagolj/Reuters)

A model presents a creation by Chinese designer Hu Sheguang from Sheguang Hu collection at China Fashion Week in Beijing, March 31, 2016. (Photo by Jason Lee/Reuters)

A dog walker on Longsands beach before sunrise in Tynemouth, UK on April 1, 2016. (Photo by Owen Humphreys/PA Wire)

A girl rides a donkey as another walks by at the Shawqaba camp for internally displaced people who were forced to leave their villages by the war in Yemen's northwestern province of Hajjah March 12, 2016. In northwest Yemen, one of the poorest countries in the Middle East, about 400 families uprooted by the war have been stuck in the Shawqaba camp in Hajjah province for the past year. Residents live in poorly built huts that protect them neither from summer heat nor winter cold in a camp that lacks the most basic services. (Photo by Abduljabbar Zeyad/Reuters)