A veteran's son received a mysterious box. It held the secret to his father's early death.

Just months after he lost his sister in 2019, Tim Miller got a call from his grieving brother-in-law.

There’s a box you should have, his brother-in-law told him.

The box had been left behind long ago by Miller’s father, who had died at an untimely age 42 years earlier — a death that had haunted his family and changed the course of Miller’s life. Though they didn’t know it then, the box would reveal the secret behind that early death.

For decades, this box had been passed around to different members of Miller’s family. First it came to Miller’s grandmother. Upon her death, the box passed to his Aunt Mary. And then to his sister, Kathi.

Whether any of them actually examined its contents, said a now-grizzle-bearded Miller, age 67 and sitting at his home just outside Rochester — looking out over autumn leaves to the waters of the Irondequoit Bay — he still doesn’t know.

Inside the box was his dad’s old sailor cap from World War II. A black-and-white photo of an unknown indigenous woman, from a faraway tropical island. A snapshot of his father during the war, the only one Miller still has from those days, shoulder to shoulder with an old Navy buddy.

And then, framed and placed under glass — with little wooden handles on each side like a harmless tea tray — was a certificate that blew open Miller’s understanding of how his father came to die so young, of a painful stomach cancer that spread to his lungs.

“Operation Crossroads,” the certificate read in folksy tiki font above a cartoon drawing of an exploding ship. “Atomic Bomb Experiment. Bikini Atoll 1946.”

Below that was his father’s name: Harold J. Miller.

At first, said Tim Miller, his response was simple wonder.

Then, he got angry.

“As soon as I made the connection that this might have had something to do with his young death,” Miller said. “49. Of cancer. That just didn't seem right. It didn’t seem right when it happened.”

Now, Miller learned, there was likely a reason his father died — a reason that had long been kept from him by order of the United States government.

“This brought all that back up: the anguish and turmoil from back then,” he said. “And then it just pissed me off.”

The 73-year secret of his father's presence at Bikini Atoll

That middle J in Tim’s father’s name stood for “Joe,” and that’s how everyone in his Erie County hometown of North East, Pennsylvania had known him.

He was a skilled inspector who could test electrical devices down to the micron, but somehow screwed up the drywall at his own house. He cared about people, said his son, but he was also a practical joker with ruthless nicknames for everyone, the kind of person who’d throw firecrackers behind you while you were trying to putt.

His family knew the old stories. How he’d lied about his age during World War II to join the Merchant Marines at 15. How he used to jump off ships to swim in ocean waters a mile deep, and had held every job in the Navy handbook from cook to pharmacist.

But Joe Miller never told the family the secret he’d kept for decades. He had been among the 42,000 sailors gathered for a perilous and fateful Cold War experiment: the detonation of two 23-kiloton hydrogen bombs in the Marshall Islands.

The Air Force hoped it would show the power of their bombs. The Navy hoped it would show its ships could withstand them.

Whatever the experiment’s conclusions, the islands of the Atoll remain uninhabitable 76 years later, its native residents still strangers to their home islands.

Sailors, even miles from the blasts, described feeling heat as if they'd gone from the shade into the sun, and an intense flash of light even through dark goggles. A pop in their ears. Sprays of water sent over the bows of their ships. Some sailors were sent to scrub decks of target ships so contaminated by radioactive water they finally had to be sunk.

More:WWII Then and Now: Feeling the atomic 'heat'

At the time, Joe Miller was an 18-year-old in a sailor’s suit. He likely didn’t know the risks. What he did know was his government told him he’d be tried for treason if he ever uttered a word.

So he never did.

“He was an honorable man,” said Miller’s wife, Karen. “He kept that vow of secrecy.”

He kept it to his death in 1977, with a funeral attended by thousands. Tim Miller had to leave Penn State to come home and care for his mother, taking the first degree he could get with the credits he had: a bachelor of arts in science.

Rather than follow his original dream into food science, he ended up doing quality assurance for some of the biggest food brands in the country.

That is, until he started to develop his own health problems. Tim Miller now suffers from stomach troubles, a pre-cancerous condition in his esophagus, an impossibly rare eye condition that led him to lose most of his field of vision and sent him to early retirement. He can’t drive a car.

His sister had similar health issues. Stomach problems. Eye problems. She succumbed eventually to pulmonary disease.

Now, he’s left wondering.

Was radiation damage to his father’s DNA passed on through their genes? Did those atomic blasts take not only his father’s, but his sister’s life, and his own vision? What if his father had been able to tell his doctor about the radiation? What if his sister had known sooner?

“Part of the nature of being in quality assurance, you start to develop a bit of a cynical streak,” Miller said. “Because things don't always just go wrong. Sometimes they happen, and people hide them.”

Atomic Veterans still learning they can talk about their experience

Stories like Miller’s aren’t unusual, said Keith Kiefer, national commander of the National Association of Atomic Veterans. Since 1979 his organization has fought to gain recognition and compensation for those exposed to ionizing radiation as part of their military service.

Nearly half a million atomic veterans are estimated to have suffered radiation exposure during a postwar testing program at Bikini and Enowatek Atolls, as well as in the Nevada desert and at underground sites in the United States. The program continued until 1992.

Kiefer himself suffered exposure cleaning up Enowatek Atoll, and for a while thereafter was ruled medically unable to have children.

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As he travels to veterans organizations around the U.S., Kiefer still finds people who don’t realize that they are Atomic Veterans — veterans who are now owed compensation from the United States government, whether because they were present for atomic tests or part of the cleanup crews.

Many more still don’t know they’re allowed to talk about it.

“Often the children or spouse of the Atomic Veteran don’t learn about their participation until they're on their deathbed,” he said.

On Oct. 3, 1995, President Bill Clinton issued a public apology to these veterans. And his administration lifted the decades-long veil of secrecy that kept them from revealing to their families — or even their doctors — that they suffered exposure to potentially cancer-causing radiation.

But by quirk of fate, this apology arrived the same day that OJ Simpson received a not-guilty verdict in the death of his ex-wife. Unless you were actually watching Clinton’s proclamation on TV, the news about Atomic Veterans got lost in the torrent, said Kathy Sinai, co-founder of advocacy organization Children of Atomic Veterans.

And so veterans held on to their secrets. Sinai found out about her own father’s radiation exposure only in 2012, after she’d asked him point-blank whether he’d been present.

“I don’t think I can talk about it,” he told her.

Now she devotes much of her life to recording the stories of these men, many of whom still have nightmares about the injustice done to the indigenous Marshallese people who lived at the sites of the tests.

Still, many veterans believe they are bound to silence. One 90-year-old veteran Sinai recently interviewed looked ominously up at the ceiling when asked about his role in the atomic tests.

“You know, they're always listening,” he said.

Delayed compensation and acknowledgment to Atomic Veterans

The long secrecy matters, said Sinai and Kiefer.

The Radiation Exposure Compensation Act (RECA), enacted in 1990, grants $75,000 in compensation to Atomic Veterans who suffered from cancer or other covered medical conditions after their radiation exposure. Uranium miners and individuals who lived downwind of test sites may also be due compensation, along with immediate descendants of veterans who died.

Among hundreds of thousands potentially eligible, fewer than 40,000 had filed successful claims as of May 2022, according to the Congressional Research Service. The program expires in May 2024.

In Rochester, the Millers say they were able to file a successful claim by reaching out to Department of Justice attorney Rebecca Krafchek, who did not respond to a request for comment.

NAAV’s Kiefer says the department of justice has been diligent in gaining compensation for victims. Miller credits especially his wife Karen Deyle Miller, a former food writer for Rochester's Democrat and Chronicle, for success in finding the right people and gathering documents.

“She's a bit of a terrier,” he said. “She finds something and she digs.”

In late 2019, the Millers held a party for the family to distribute much of the $75,000 to his sister's daughters and husband.

He would rather have had more years with his father. More years with his sister. But he hopes the money can still be of use to his nieces.

The science still isn’t in on whether his own health problems, or those of other children of Atomic Veterans, might stem from the radiation exposure. In 1995, the U.S. Institute of Medicine convened a committee to outline a study on the effects of radiation on the estimated 500,000 descendants of Atomic Veterans.

But the committee stopped this study before it began, citing “insurmountable difficulties” in finding enough offspring of Atomic Veterans, and estimating radiation exposures.

This July, President Biden announced a much-belated medal owed to Atomic Veterans like Miller’s father. Alongside Veterans Day in November, July 16 would henceforth be Atomic Veterans Day.

“For far too long, our nation failed in our sacred obligation to our Atomic Veterans,” Biden said. “It is a mistake our country must never repeat.”

For Miller, the medal is not what matters. Neither, really, does the money.

But the money does serve, at least, as an apology. And by telling his story, he hopes he can help alert other veterans and families that they’re due the same.

“The most important thing is not the recognition that my dad might have gotten,” he said. “It’s that more people have the right to this compensation. And that the government is thus acknowledging that yes, we put these people in harm's way.”

He thinks of his father, still just a teenager in a sailor’s cap who carried around a snapshot of a woman he’d seen one day on an island, ordered to float near a nuclear detonation.

“They used these guys as lab rats.”

Matthew Korfhage writes about culture, food and equity for the USA TODAY Network's Atlantic Region How We Live team. Follow him @matthewkorfhage on Twitter or email mkorfhage@gannettnj.com.

This article originally appeared on USA TODAY NETWORK: Atomic veteran's son finally learns secret behind father's early death