ARLINGTON, VA. — Col. Bud Day, one of the military’s most decorated war heroes and a longtime veteran’s activist who settled in Northwest Florida after his retirement from the Air Force in 1977, was promoted posthumously Friday to the rank of brigadier general.

Day, who died in 2013 at the age of 88 at his home in Shalimar following a long battle with cancer, was a veteran of World War II and the Korean and Vietnam wars. He was held as a prisoner of war in Vietnam for nearly six years. During his time in captivity, Day met Sen. John McCain, R-Arizona, then a lieutenant commander in the Navy, and helped nurse a badly injured McCain back to health. The two remained close throughout Day's life.

Among the 70 medals Day earned was a Congressional Medal of Honor he received for escaping and evading capture by the Vietnamese, and refusing to provide them with information that would have compromised American missions. He was eventually recaptured and held at the infamous Hanoi Hilton.

Day's promotion to brigadier general was included as a provision of the 2017 National Defense Authorization Act, the federal military spending bill.

“Brigadier General Bud Day is a true American hero, and I can’t think of anyone more deserving of this distinct honor," said U.S. Rep. Matt Gaetz, R-Fla., who represents Northwest Florida in Congress. "Recognizing his tremendous sacrifice in service of our great nation is a testament to the impact he had, and is our way of saying ‘Thank you’ to his family."

During a Friday evening promotion ceremony at the Air Force Memorial, Gaetz called Day "a national treasure, and a local hero in Florida’s First Congressional District."

"His legacy will live on for generations to come,” Gaetz said.

During his military career, Day served with the Marines, the Army and the Air Force. He was with the Marines in the Pacific Theatre in World War II and served as an Air Force pilot in Korea and Vietnam.

Day had a matter-of-fact attitude about his military service, his work as a lawyer and his community service.

“It’s what you are supposed to do,” Day said at his 88th birthday party. “Courage, dignity — that stands for something.”

In a statement released at the time of Day's death, McCain called Day "the bravest man I ever knew, and his fierce resistance and resolute leadership set the example for us in prison of how to return home with honor.”

Day was born in Sioux City, Iowa, on Feb. 24, 1925. He enlisted in the Marine Corps in 1942 during World War II while he was still in high school. After the war, he attended college on the GI Bill, earning a bachelor’s and law degrees in four years. He joined the Army Reserve and then switched to the Air Force where he learned to fly, piloting air defense F-84s in Korea and the fighter-bomber F-100 in Vietnam.

Day retired from the Air Force in 1977 and became a champion for veterans of all wars. One of his most high-profile efforts was his work to secure TRICARE medical benefits for veterans of World War II, Korea and Vietnam.

Three years ago, the Bud and Dorie Day Patriots' Trail, a walking path in Fort Walton Beach dedicated to Day and his wife, Dorie, was opened. The trail, from Staff Drive to Ferry Park, marks various periods in Day's life and includes a Freedom Memorial and a garden dedicated to Dorie Day.