Maj. Matt O'Donnell of Glenelg, MD shields himself from rotor wash as Ospreys carrying the delegation of U.S. Secretary of Defense Leon Panetta leaves on March 14, 2012 at Forward Operating Base Shukvani, Afghanistan. Panetta is also scheduled to meet with President Karzai during his two-day visit to Afghanistan. The trip comes as the Taliban has vowed revenge following this past weekend's killing spree by a U.S. soldier who is accused of killing 16 civilians in Afghanistan. Most of those killed were children and women. (Photo by Scott Olson/Getty Images)

Kathleen Darling, wife of disabled veteran Caleb Darling, celebrates a shot during a sled hockey game on March 29, 2012 in Aspen, Colorado. (Photo by John Moore/Getty Images)

U.S. Army Sgt. Patricia Foust receives a free Christmas tree on December 7, 2011 at Fort Carson in Colorado Springs, Colorado. More than 600 soldiers and military families at the base chose trees as part of the annual Trees for Troops program. (Photo by John Moore/Getty Images)

“Derby”, Kentucky Gallahue's goldendoodle, of Point Loma, sporting a mohawk haircut and sunglasses, leaps off the surfboard during the 2018 Imperial Beach Surf Dog Competition next to the Imperial Beach Pier in San Diego, California on July 28, 2018. (Photo by Howard Lipin/San Diego Union-Tribune via ZUMA Press/Rex Features/Shutterstock)

Nina Leen, one of the first female photographers to work for Life, took pictures for the magazine from 1940 to 1972. In the mid-1940s, her essay, “City Dogs”, featured actors and artists with their pets on the streets of New York City. In late-March, Daniel Cooney Fine Art in New York City, is opening a solo exhibition of Leen’s work that features images from that essay and others. Here: author Fannie Hurst clad in mink coat, enjoying the jumping antics of her Yorkshire terrier Orphan Annie on the street. (Photo by Nina Leen/Pix Inc./The LIFE Picture Collection/Getty Images)

Militant Islamist fighters take part in a military parade along the streets of Syria's northern Raqqa province June 30, 2014. The fighters held the parade to celebrate their declaration of an Islamic “caliphate” after the group captured territory in neighbouring Iraq, a monitoring service said. The Islamic State, an al Qaeda offshoot previously known as Islamic State in Iraq and the Levant (ISIL), posted pictures online on Sunday of people waving black flags from cars and holding guns in the air, the SITE monitoring service said. (Photo by Reuters/Stringer)

A student attending a winter military camp reacts during a training session in Ansan, south of Seoul January 3, 2013. Hundreds of students between 11 and 17 years old attend winter boot camp training courses every year. The winter courses range from 4 to 14 days at the Blue Dragon Camp run by retired marines, which also offers summer boot camp for students. (Photo by Kim Hong-Ji/Reuters)