After 70 years, the children of one missing Korean War airman have not given up on America's promise to its service members and their father -- to leave no one behind.

In 1952, Air Force Lt. Hal Downes, a navigator and radar operator, was shot down over North Korea. His body was never recovered.

His son, Richard Downes, was three years old when his father was lost.

"We have to guard against the official rhetoric," Downes told correspondent Lara Logan on her Fox Nation show "Lara Logan Has No Agenda." "They say no man left behind, but we've left many behind and for decades."

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Downes is president and executive director of the Coalition of Families of Korean & Cold War POW/MIAs. While he is realistic about the nature of America's duty to its service members, he also works with the U.S. government to try and determine the fate of missing troops.

"[Downes] and his sister have fought for decades on behalf of all the families waiting to bury their dead," narrated Logan, "holding the U.S. to its commitment to leave no man behind. Etched into the stone of the Korean War Memorial in Washington, D.C., his father's face."

The American tradition of returning U.S. war dead to their families for burial is a relatively recent one for the country and for humankind in general.

"It wasn't always this way for thousands of years," observed Logan. "Fallen soldiers were mostly abandoned in the field."

"That's how it was in the American Revolution," she continued, "but the devastation of the Civil War changed that forever."

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Congress passed a law in 1862 establishing burial grounds for some of the more than 625,000 men who died fighting in the Civil War. This recognition of the importance of recovering the bodies of the dead was later extended to U.S. troops who died overseas.

"The tradition, now sacred, of leaving none behind rose out of the ashes of the First Great War," said Logan, "when the families of the fallen would not be denied the chance to bury their dead."

The Pentagon's Defense POW/MIA Accounting Agency (DPAA) is tasked with the mission of recovering missing personnel listed as prisoners of war or missing in action.

Logan spoke to the deputy of outreach and communications for the DPAA, Johnie Webb, a Vietnam veteran himself.

"If you go back to World War II to present day, there's just under 82,000 [service members] that are still out there somewhere that never made it back home," Webb told Logan, describing the scope of the DPAA mission.

"A number of those World War II losses are naval losses, deep-sea losses that we don't have the technology and capability to go recover those individuals," he continued. "We believe that there are some 34,000 that are still recoverable. And that's still a huge number."

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The work is slow and painstaking. Often only bone fragments are recovered, requiring sophisticated analysis to determine if they are truly the remains of a missing person.

However, regardless of the condition of the remains, the missing are treated with the honor and respect that Americans have come to expect for their fallen.

"We never bring any, any remains back that there is not some type of ceremony," said Webb. "Doesn't matter if it's 2 o'clock in the morning when the aircraft arrives, we will have personnel out there to render honors to those individuals that are coming off that aircraft... "

To watch all of this episode "No Agenda with Lara Logan," and learn more about the work of the DPAA, go to Fox Nation and sign up today.

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