In the summer of 2003, not long after U.S. forces had taken Baghdad, a group of Marines was clearing unexploded ordnance in central Iraq when one of the small grenades littering the ground detonated.
It was a cluster munition dud left over from an American attack, the same type of weapon that the United States is now sending Ukraine.
A Marine bomb technician lost his left hand, part of his right hand, his left eye and most of his right leg in the explosion.
Metal fragments also blasted into the torso and neck of Lance Cpl. Travis J. Bradach-Nall, a 21-year-old combat engineer who was standing guard about six feet away. He died minutes later.
The Marines were experts in their craft, trained for missions like these, and still there was an accident. The cheaply made grenades they were clearing were more hazardous than many other types of weapons they could encounter on the battlefield — easily hidden by debris, dirt or sand, and built with simple fuzes that could cause them to detonate if jostled.
Their task that day was made even more difficult by the sheer scale of the mess they had to clean up. A photo taken at the site for an investigation shows an old wooden ammunition crate packed with roughly 75 similar unexploded American grenades that the Marines had already rendered safe.
Mass produced toward the end of the Cold War, cluster munitions of this type scatter dozens or even hundreds of the tiny grenades at a time. These grenades were designed to destroy enemy tanks and soldiers deep behind enemy lines on land where allied soldiers were never meant to tread.
U.S. government studies have found that the grenades have a failure rate of 14 percent or more, meaning that for every 155-millimeter cluster shell that is given to Ukraine and fired, 10 of the 72 grenades it disperses are likely to fall to the ground as hazardous duds.
More than 100 nations have banned their use because of the harm they pose, especially to children, but the United States, Russia and Ukraine have not.
In July, the Biden administration decided to provide artillery shells of this type to Ukraine after officials in Kyiv assured the White House that their forces would use them responsibly. Ukraine also promised to record where they used the shells for later demining efforts.
The decision was frustrating and painful for some American civilians who have dealt with the aftermath of their use in combat.
Lynn Bradach was driving near Portland, Ore., in early July when she heard the news on the radio, almost exactly 20 years after the same weapon killed her son, Lance Corporal Bradach-Nall.
“I was like, ‘I can’t believe this.’ It’s just absolutely insane,” said Ms. Bradach, who spent years advocating a global ban on cluster weapons after Lance Corporal Bradach-Nall’s death.
A few weeks ago in Oregon, on the banks of the Zigzag River, she said a final goodbye to her son. She had spread some of his ashes at places he loved in life, and released the rest into the water.
The White House’s decision reopened old wounds for some American veterans as well.
Early on Feb. 27, 1991, with the cease-fire that would end the Persian Gulf war just a day away, Mark P. Hertling, a major at the time, was talking with soldiers near his Bradley Fighting Vehicle.
“It was raining, dark as hell — no moon, and it was windy,” he said. “I heard five pops in the air and thought, ‘What the hell was that?’”
It was the sound of friendly fire — artillery shells each disgorging their loads of 88 grenades overhead.
“The next thing, within seconds, it was like being in a popcorn machine popping,” he recalled.
Mr. Hertling was one of the 31 soldiers wounded by the swarm of exploding grenades, two of whom had to be medically evacuated. Several vehicles were damaged but none were destroyed.
The soldiers moved on, but they were not done dealing with the lethal detritus of unexploded American cluster munitions before they could redeploy back home.
“We were blowing up weapons caches after that, and there were D.P.I.C.M. duds everywhere,” Mr. Hertling said, using the military’s name for the grenades, which are formally called dual-purpose improved conventional munitions. “I can’t put it any way other than that. We would be driving through an area and there they were.”
For the rest of his career, Mr. Hertling, who retired as a lieutenant general, wore the Purple Heart medal he earned in the attack for wounds from an American cluster weapon.
Twelve years later, in the initial phase of another war in Iraq, Seth W.B. Folsom was told to get his light-armored reconnaissance unit off the highway hours after it left a temporary camp near the town of Diwaniyah.
Then a Marine captain in command of a company, Mr. Folsom ordered a squad to do a quick sweep of the area for potential threats before the rest of his Marines could leave their vehicles.
Soon after they set off on foot, one of the Marines in that patrol, Lance Cpl. Jesus Suarez del Solar, went down in an explosion.
“Initially we thought it might have been a mortar or a hand grenade, but when we looked at his gear and the wounds he suffered we realized he bumped into something with his foot,” Mr. Folsom said. “It shredded his foot in half; his whole lower body was peppered with wounds.”
“He suffered a pretty substantial wound to the inside of one of his legs, and it severed his femoral artery,” he said. “All our efforts were to stop that wound.”
Mr. Folsom soon realized he was surrounded by dud cluster weapon grenades that had recently been used against Iraqi soldiers.
“Once you knew what to look for, you saw them everywhere,” he said.
According to procedures, everyone in the battalion should have been warned over the radio about any use of cluster munitions in the area so that maps could be marked.
That call never happened.
Lance Corporal Suarez del Solar bled to death while being evacuated on March 27, 2003.
Darkness fell, and the captain ordered his Marines to stay in their armored vehicles overnight until bomb technicians could arrive and blow up remaining duds in the area.
“That 24 hours after the episode, there was a lot of shock, a lot of grief and a lot of anger we couldn’t direct anywhere,” Mr. Folsom said. “If a Marine dies of enemy fire, you can direct that anger at the enemy.”
“If it’s friendly ordnance, who do you direct that anger to?”
The episode stayed with Mr. Folsom through the rest of his career in the infantry, as he gave safety briefings during additional combat deployments. He retired as a colonel in January and has been watching the public discussions about sending the weapons to Ukraine.
“My feelings about this issue are very ambivalent,” he said. “I’ve got very highly charged feelings for and against, and it’s all because I have a natural bias — I have skin in the game.”
Mr. Folsom takes responsibility for Lance Corporal Suarez del Solar’s death.
“That’s something that I can’t forget,” he said. “People really need to understand the human element of that decision that’s been made.”
Mr. Folsom and Mr. Hertling, veterans of multiple combat tours, both expressed concern that, in the rush to keep Ukraine supplied with artillery ammunition, the risks regarding cluster weapons could be papered over.
“What revolts me is the whataboutism, focused on the fact that Russia has been using these weapons from the beginning of the war,” Mr. Folsom said. “So what? That doesn’t make it right.”
Mr. Hertling said he understood the Pentagon’s decision if there were shortages of regular high-explosive shells available for Ukraine’s counteroffensive, which began this summer.
But he is frustrated by people who minimize the danger.
“There’s millions of unexploded munitions already in Ukraine; there’s thousands of mines that have been laid by the Russians,” he said. “Now what we’re hearing from people is, ‘Oh, what the hell — another couple hundred thousand U.S. D.P.I.C.M., that’s no big deal.’”
“Yeah, it’s no big deal — until some kid picks it up and says, ‘Hey look at this,’” he said.
Mr. Folsom wants Ukraine to retake its sovereign land, but he knows the risks the shells will pose to Ukrainian soldiers and civilians for years to come.
“I just hope they understand what they’re asking for,” he said.