Defense Secretary Pete Hegseth decided in early 2025 to spike Gen. Christopher T. Donahue’s nomination to be the top U.S. military officer in Europe.

Mr. Hegseth believed that President Trump wanted heads to roll for the deaths of 13 U.S. service members in a suicide bombing at the Kabul airport during the U.S. withdrawal from Afghanistan in 2021. General Donahue was not responsible for security at the bombing site. But he was a top commander at the airport, and so Mr. Hegseth decided he needed to go.

It fell to Joe Kasper, Mr. Hegseth’s chief of staff, to try to convince him that he was wrong.

Mr. Kasper asked a senior Pentagon official to prepare a card with a half-dozen bullet points laying out the facts in General Donahue’s defense, current and former officials said. He took it with him in March of last year as he and Mr. Hegseth sped through traffic to the White House for a press event.

For those few minutes in the car, Mr. Kasper knew he would have his boss’s undivided attention.

Sirens were blaring. He handed Mr. Hegseth the card.

These were the facts of General Donahue’s three-decade career: He had seen more combat in his 20-plus deployments than just about any officer in the U.S. military. A star in the clandestine world of special forces, he had spent years in the shadows hunting terrorist leaders. And then as the world and warfare changed, he changed with it.

He had played a central role in the U.S. military’s efforts to help Ukraine hold off a much larger Russian force, a job that inspired his vision for a new kind of combat that married divebombing drones, robotics and artificial intelligence.

Now his fate lay in the hands of Mr. Hegseth, a former Fox News host who had two deployments as an Army officer to Iraq and Afghanistan. Mr. Hegseth had come to the Pentagon vowing to weed out the “small” and “feeble” generals who he believed had failed in those wars.

What played out in the 16 months after the car ride was a clash between Mr. Hegseth and General Donahue’s supporters, who viewed him as a generational talent.

That clash, and its outcome, was described to The New York Times by more than 40 people at the Pentagon, in Congress and around the world, nearly all of whom spoke on the condition of anonymity to avoid retribution.

It amounts to one of the most consequential chapters in Mr. Hegseth’s campaign to drive out those he sees as out of step with his priorities, a leadership purge that his critics say is driven by ideology, identity and suspicion of those with tenuous ties to former military leaders that he does not like. And it shows the intensity of the behind-the-scenes battle to save one general.

The more General Donahue’s allies pushed, the more Mr. Hegseth’s opposition seemed to harden.

The Pentagon declined to answer questions about General Donahue, saying in a statement that all senior military leaders serve at the pleasure of the president and the defense secretary.

In the spring of 2025, General Donahue was commanding ground forces in Europe. Mr. Hegseth was new to the Pentagon. To the extent he was familiar with General Donahue, it was largely through the prism of the Afghanistan withdrawal and a grainy photo that indelibly linked the general to the war’s tragic end.

General Donahue was the last U.S. soldier to leave Afghanistan. As he stepped onto a hulking military cargo plane, an Army photographer snapped his picture using his cellphone camera and night vision device.

The green-and-black image rocketed around the world. Senior Pentagon officials said Mr. Hegseth seemed to be fixated on the photo, mistakenly referring to it as a “selfie.”

The first item on the card that Mr. Kasper handed to Mr. Hegseth in the car clarified that the photo was not a selfie and that General Donahue had nothing to do with its distribution. Other bullet points noted that Marines, not General Donahue’s paratroopers, were in charge of the gate where the suicide bombing occurred.

The defense secretary glanced at the card and passed it back to his chief of staff.

“I don’t care,” Mr. Hegseth told Mr. Kasper.

‘Brother, We Need Your Help’

At first, General Donahue wasn’t supposed to go to Afghanistan for the withdrawal. The Pentagon said it just needed roughly 2,000 of his paratroopers from the 82nd Airborne Division to help with security at the Kabul airport.

Then, on Aug. 16, 2021, shortly after the paratroopers started arriving, thousands of Afghans, desperate to escape Taliban insurgents, swarmed the runways, preventing planes from taking off and landing.

General Donahue’s paratroopers watched in horror as Afghan special operations units, who were waiting to be evacuated, beat back the civilians so that flights could resume.

Amid the chaos, General Donahue got new orders: Get to Kabul as fast as possible.

Three decades had passed since General Donahue graduated from West Point. He was in his mid-20s when his leadership skills and football player’s build caught the eye of a senior officer in Delta Force, the Army’s elite counterterrorism unit.

He survived the selection process and disappeared into a world of secrecy and fake personas. Deployments to Iraq, Afghanistan, Syria and other hot spots followed as he rose to become Delta’s top commander.

The skill that often set General Donahue apart from his peers on those battlefields was his ability to win the trust of local partners. It had been on display in Afghanistan in May 2019 when he began leading special operations forces in the country and won over his Afghan counterpart, Brig. Gen. Sami Sadat.

Together, they leveraged airstrikes, special operations advisers and commandos to punish Taliban insurgents and retake territory that had been lost. “We didn’t feel like we cracked the code; we did crack the code,” General Sadat said.

But their battlefield gains were fleeting. In February 2020, Mr. Trump cut a deal with the Taliban to curtail U.S. military support to Afghan forces and begin the American withdrawal.

General Sadat remembered sitting by General Donahue’s side in their command post watching a drone feed as the Taliban rolled over an Afghan unit. “He was very angry, frustrated and ashamed,” General Sadat said.

Eighteen months later, the Afghan president had fled the country and the government had collapsed. General Sadat reconnected with General Donahue, who was already on his way back to Afghanistan, and told him that his Afghan forces had dissolved.

“Brother, we need your help,” General Sadat recalled telling him.

General Donahue landed in Kabul on Aug. 17.

Around 2 a.m., he met with Qari Hamdullah Mokhlis, a Taliban commander whom General Donahue’s commandos had been trying to find and kill as recently as 2020. The general’s former target was now his partner.

“You don’t like me; I don’t like you,” General Donahue’s paratroopers recalled his telling the Taliban commander. “But we’re going to have to work together.”

The biggest threat to both was the Islamic State terror group, which was determined to turn the withdrawal into a blood bath, according to U.S. intelligence. The U.S. military would control the airport and its entry gates. U.S. commanders wanted the Taliban, who had set up checkpoints outside the airport, to let American citizens and allies pass through, and keep out would-be suicide bombers.

General Donahue’s paratroopers began preparing for a major attack. They cleared the roads leading to the airport’s field hospital so they would be able to rush wounded to get care.

The intelligence identified Abbey Gate, a major airport entry point controlled by the Marines, as the most likely target. The Marines were planning to leave and turn over control of the site to General Donahue’s troops.

On Aug. 24, General Donahue visited the gate and saw thousands of desperate Afghans crowding the Marines who were trying to maintain order and screen them.

The chaos and proximity between the Afghans and the Marines made it an ideal target for a suicide bomber, General Donahue told his paratroopers.

The plan was for General Donahue’s paratroopers to take control of Abbey Gate from the Marines on Aug. 27 and shut it down. But General Donahue thought it was too risky to wait. He met with the senior U.S. commander at the airport and recommended shutting the gate immediately.

British forces, which were using the entryway to evacuate their citizens and allies, asked the Americans to keep it open. Pentagon leaders “grudgingly” agreed, a senior U.S. official recalled.

The Marines were still in control of Abbey Gate at 5:48 p.m. on Aug. 26 when the suicide bomber struck. Eleven Marines, one Navy medic and one Army soldier, along with scores of Afghans, were killed.

General Donahue could hear and feel the blast at his headquarters on the other side of the runway. “I need to know the numbers and types of casualties,” he told his staff. The situation was so dire that medics began pumping blood from healthy soldiers into the veins of the wounded.

On Aug. 30, America’s longest war came to a bitter end. General Donahue took a parting glimpse at the Kabul airport and then hurried onto the big, gray plane. It was the last one out and, in keeping with Army tradition, he was the final soldier to board. The Army photographer captured the moment at 11:46 p.m. using his iPhone and the night vision monocle attached to his helmet. When the plane landed in Qatar, General Donahue called his wife.

His paratroopers overheard the conversation.

“We’re out,” he said.

“I know,” she said.

“How did you know?” he asked.

“Everybody knows,” she said.

She sent him the photo, which was now posted on news sites around the world. General Donahue, taken aback, showed the photo to members of his team. He had spent most of his career in the shadows. Now he was everywhere.

“This is not good,” he said.