Lt. Larry Young, dressed as Santa, signals to launch an F/A-18E Super Hornet on the flight deck of the aircraft carrier USS Theodore Roosevelt. U.S. Navy Mass Communication Specialist 3rd Class Victoria Foley

A waterspout forms as the USS Gerald R. Ford travels in the Atlantic Ocean on December 4. Navy photo by Petty Officer 2nd Class Martin Widenhouse

Marines conduct a low-light deck shoot to maintain marksmanship proficiency while underway aboard the amphibious assault ship USS America. Lance Cpl. Dusty B Kilcrease

A special missions aviator assigned to the 46th Expeditionary Rescue Squadron inspects the blades on an HH-60G Pave Hawk helicopter tail rotor prior to a sortie on November 22, in an undisclosed location. U.S. Air Force Staff Sgt. Joshua Kleinholz

US Vice President Mike Pence speaks to troops in a hangar at Bagram Air Base in Afghanistan on December 21. Mandel Ngan/AP

Navy Petty Officer 1st Class Corey Oliver hugs his daughter in San Diego on December 5, following a regularly scheduled deployment aboard the USS Nimitz to the Western Pacific. Navy photo by Seaman Apprentice Jailene Casso

Paratroopers take cover while conducting live fire training with fragmentation grenades at Joint Base Elmendorf-Richardson in Alaska on December 12. Senior Airman Curtis Beach

Lightning strikes near the aircraft carrier USS Theodore Roosevelt as it travels in the Persian Gulf on December 16. 1st Lt. Mark Vetere

Navy Petty Officer 2nd Class Chris Carlson performs underwater cutting operations while working with divers assigned to Underwater Construction Team 2 in Apra Harbor, Guam, on December 11. Navy photo by Petty Officer 1st Class Arthurgwain L. Marquez

President Donald Trump greets World War II veteran Lawrence Parry before signing a proclamation for National Pearl Harbor Remembrance Day with survivors of the attack. The Washington Post/Getty Images

The USS Constitution's 75th Commanding Officer Commander Nathaniel Shick, left, and Pearl Harbor survivors Freeman K. Johnson and Emery Arsenault, commemorate the 76th anniversary of the attack on Pearl Harbor at the Charlestown Navy Yard in Boston. Boston Globe/Getty Images

Marine Corps Cpl. Seth Witherup signals to a pilot during training at California's Naval Air Facility El Centro on December 6. Marine Corps Cpl. Carlos Jimenez

Air Force Airman Jasmine Castaneda fires an M-240 during weapons training at Beale Air Force Base in California on December 20. Air Force Senior Airman Colville McFee

Army quarterback Ahmad Bradshaw and the Chief of Staff of the Army Gen. Mark Milley raise up the Commander in Chief's Trophy at the Army Navy Game in Philadelphia. Army beat Navy for the second straight year, 14-13, on December 9. U.S. Army John Martinez

Starlings pass in front of the Washington Monument and the Marine One helicopter, as President Donald Trump returns to the White House from Walter Reed Medical Center on December 21. The Washington Post/Getty Images

First Lady Melania Trump sits with 3-year-old Mehreem Donahue in her lap, as she makes Christmas cards with military kids at the Marine Corps' annual Toys for Tots event on December 13. Cheriss May/NurPhoto via ZUMA Press

Members of the US military are served dinner on Christmas Day at the Resolute Support Headquarters in Kabul, Afghanistan on December 25. Rahmat Gul/AP

A sailor walks across the flight deck of the aircraft carrier USS John C. Stennis after being relieved from watch while the ship is port in Bremerton, Washington, on December 25, preparing for its next deployment. Seaman Erika Kugler

Wreaths lie on memorial markers during the Wreaths Across America event at Arlington National Cemetery on December 16. Elizabeth Fraser/Arlington National Cemetery

President Donald Trump talks with retired Marine Sgt. John Peck and his wife Jessica during a visit to meet with wounded service members and their families at Walter Reed National Military Medical Center on December 21. Peck is a quadruple amputee, and has received a double arm transplant. Evan Vucci/AP