Originally Published: 05 JUL 22 11:27 ET

Updated: 05 JUL 22 12:56 ET

By Maegan Vazquez and Oren Liebermann, CNN

(CNN) -- President Joe Biden on Tuesday bestowed the Medal of Honor to four Army veterans who fought in the Vietnam War, upgrading previous honors they had received for their acts of valor.

The individuals who received the medal -- the most prestigious decoration in the US military -- are Staff Sergeant Edward N. Kaneshiro, Specialist Five Dwight W. Birdwell, Specialist Five Dennis M. Fujii and retired Major John J. Duffy.

"They stood in the way of danger, risked everything ... to defend our nation and our values," Biden said during the ceremony at the White House. "However, not every service member has received the full recognition they deserve. Today we're setting the record straight. We're upgrading the awards of four soldiers who performed acts of incredible heroism during the Vietnam conflict."

The President said it's been a long journey -- more than 50 years -- for those veterans and their families. "But time has not diminished their astonishing bravery, their selflessness in putting the lives of others ahead of their own and the gratitude that we as a nation owe them," he added.

In 1966, Kaneshiro and members of his platoon were attacked by North Vietnamese when they entered a village on a search and destroy mission. According to the White House, "Kaneshiro destroyed one enemy group with rifle fire and two others with grenades, which enabled the orderly extrication and reorganization of the platoon and ultimately led to a successful withdrawal from the village." Kaneshiro, who was killed in action three months after the incident for which he is being awarded, will receive the award posthumously.

"Your family sacrificed so much for our country," Biden told Kaneshiro's family. "I know that no award can ever make up for the loss of your father and not having him there as you grew up. But I hope today you take some pride and comfort in knowing his valor is finally receiving the full recognition it has always deserved."

Before receiving the award on his father's behalf, Kaneshiro's son told CNN that his dad's story inspired his own career in the military.

"Just to imagine ... for him to just be selfless and to just jump into the fire like that. It inspired me to ... live up to what he has done," John Kaneshiro said.

Birdwell, a former Cherokee Nation Supreme Court justice, received the medal for his actions in January 1968.

At an air base near Saigon on the first day of what would become known as the Tet Offensive, Birdwell and his unit were under assault by North Vietnamese. While under fire, he moved a tank commander to safety and fired the tank's weapons at enemy forces, according to the White House. When the tank weapons were exhausted, he dismounted and moved to a downed helicopter to retrieve ammunition and machine guns with a comrade. Birdwell's machine gun exploded when it was struck by enemy rounds, injuring his face and torso, but he refused to evacuate and led a small group to disrupt the attackers. He then helped evacuate the wounded until ordered to seek attention for his own injuries.

"I did the job that I was trained for. I felt like I had to do this. It was a matter of duty. And I did my duty as best I could," Birdwell said. "I've wondered a thousand times why I survived and some of the others didn't, but I've thought when I go up for judgment, if I have the courage, I'll ask God that question."

Biden described how "it took decades" for Birdwell's commanding officer, Gen. Glenn Otis, to realize he "had not received the full honor he had earned." But in retirement, Biden said, "Gen. Otis made sure to correct the record and fully document Birdwell's actions to make this day possible."

Fujii received the medal for his actions during a helicopter ambulance rescue in Laos and Vietnam across four days in February 1971.

Aboard a helicopter during a mission to evacuate seriously wounded Vietnamese military personnel, the aircraft took on enemy fire and was forced to crash land, according to the White House. As he was injured, Fujii waved off another helicopter and was the only American to remain behind on the battlefield. He repeatedly exposed himself to enemy fire, administered first aid to allies and called in US helicopter gunships to repel enemy attacks.

Duffy received the award for his acts in Vietnam in April 1972.

Injured at his battalion's destroyed command post in South Vietnam, where the battalion commander had been killed, Duffy refused to be evacuated. There, he "led a two-day defense of the surrounded FSB against a battalion-sized enemy force," according to the US Army. He exposed himself to the enemy to call in airstrikes and was injured again when struck by the fragments of a rifle round. But Duffy stayed, directing helicopter gunships onto enemy anti-aircraft and artillery positions. He then personally ensured that wounded troops were moved to safety and distributed ammunition. And during a ground assault by enemy forces, Duffy moved several times to spot targets. Later, he led more wounded troops to evacuation "while in continual pursuit by the enemy," the Army states.

Biden also described how as their airship was preparing to depart, one of Duffy's Vietnamese allies was shot in the foot, "causing him to fall backwards out of the helicopter."

"Maj. Duffy caught him and dragged him back in on board, saving one more life along the way," he continued.

Duffy, who is now 84 years old, was deployed to Vietnam four times, racking up 64 awards and decorations -- including 29 for valor, four Bronze Stars, eight Purple Hearts and seven Air Medals.

"You're honor-bound to do your duty, and it doesn't matter the risk or the danger. You're there to perform. And as long as you do that, you're in control," Duffy said ahead of being awarded the Medal of Honor.

Tuesday's ceremony comes a week after the last surviving World War II Medal of Honor recipient, Hershel W. "Woody" Williams, died at the age of 98. Williams will lie in honor at the US Capitol.