Elliot Ackerman is the author of several books, most recently the forthcoming novel "Waiting for Eden."

A German Bundeswehr soldier on International Security Assistance Force deployment patrols high ground and searches for improvised explosive devices during a regular patrol near Mazar-e-Sharif, Afghanistan in 2010.  (Miguel Villagran/Getty Images)

“Something has to be done,” President Trump said Wednesday at the NATO summit in Brussels, referring to the fact that only five of the 29 member countries are meeting their pledge to allocate 2 percent of GDP to their militaries. Later, he took to Twitter to demand that member countries get to that level of commitment “IMMEDIATELY, not by 2025.” He then accused Germany of being “captive to Russia.” And by the end of the day Trump suggested that, perhaps, a 4 percent expenditure of GDP on defense spending would be a more appropriate commitment for nations that wish to continue to be members of NATO.

Discrepancies in commitment have always plagued NATO. The administrations of both George W. Bush and Barack Obama wrestled with this issue. President Trump seems determined to adopt a hard stance against delinquent NATO members, shaming them into submission. This hard stance isn’t unwarranted, but his method might not be effective.

Article 5 of NATO, which states that “an attack on one is an attack on all,” was invoked for the first time after the 9/11 terrorist attacks, leading to the creation of ISAF, or the International Security Assistance Force, in Afghanistan. At any given time since, there have been around 10,000 troops from NATO-member countries serving in Afghanistan.

Ten years ago, as a special operator working on a remote firebase in western Afghanistan, far from the larger U.S. presences in the south and the east, I was particularly reliant on our allies. It wasn’t easy. Certain members of the alliance presented significant challenges by adopting policies that protected a country’s soldiers at the expense of U.S. troops, with some member nations refusing to fight in certain circumstances.

NATO’S ineffectiveness in Afghanistan has been well documented, yet many troops from NATO have fought bravely; two British soldiers have been awarded the Victoria Cross. Combat is complicated — and so is diplomacy.

Hearing Trump’s remarks brings to mind one incident in particular: an ambush.

Our team of special operators and our Afghan counterparts had been up for almost two days as we drove back from a mission. Our route passed through a village with a single road crowded with mud-walled compounds. The first rocket hit the vehicle in front of mine. Our Humvee was peppered with machine-gun fire. As we fired back, our convoy moved as fast as it could down the single road, which was the kill zone of the ambush. Of the 11 vehicles we’d entered the village with, four were left inoperable, and a fifth was destroyed. One of our own had been killed, and a dozen of us had been wounded.

We were a six-hour drive from our firebase. It was getting dark. Of our myriad problems, the most pressing was arranging medical evacuations. We had formed a perimeter a few hundred meters outside the village, where the Taliban continued to take potshots at us. When we called in our medevac, we were asked whether the landing zone was “hot” or “cold.” It was still hot.

A voice with a non-American accent informed me that policy prevented medevacs from being sent into hot landing zones. Could I please secure the landing zone? the voice wanted to know. Or, if I could not secure the landing zone, could I please move?

I now demanded a medevac.

I received the same answer.

I called my higher command, who explained that the NATO-member country that was currently on rotation for medevac duty had this restriction placed on its troops’ involvement and that our American command was doing the best it could to source a medevac from somewhere else.

Minutes passed into hours. The back and forth on the radio hardly stopped. The Taliban kept taking potshots at us.

Then, out of nowhere, a voice popped up on our net. It was American. A pair of Blackhawk helicopters on a totally unrelated mission had heard our calls. Did we need some help? The pilots immediately diverted. Within 15 minutes they had touched down and our wounded were loaded on board.

Our convoy limped back to base. We arrived the following morning, our trucks shot out, one dead friend, and more wounded, some of whom would return to us and others who wouldn’t. We were in a sour mood. The source of our ire fell distinctly on the medevac that had failed to arrive.

The next day, the Special Forces colonel we worked for, a fair and well-respected commander, showed up at our firebase. He wanted to check up on us. I wanted to give him a piece of my mind about the medevac. I had fantasies of him driving to ISAF headquarters in Herat, storming into the command center and dressing down our cowardly allies who refused to fly for us that day. He could tell where my mind was at when he revealed that he had a trip to Herat planned.

“I’m not going up there to chew ass,” he said. “I’m going to go up there to thank them.”

For what? I wanted to know.

“They’re soldiers, like us,” he explained. “You think those pilots and those medics didn’t want to fly into a hot LZ for you? It’s all they want. They feel ashamed that they can’t.” He then told me that’s why he was going to thank them, because they’d done everything they could to convince their higher commanders to let them help us that day, even though, ultimately, they hadn’t been successful.

The levels of commitment of certain NATO-member countries are problematic; they have been for a long while. However, I doubt President Trump’s new approach will yield the desired result. Certainly, the gentler approach favored by both the Bush and Obama administrations hasn’t seemed to work, but I remain doubtful that shaming allies makes them better allies.

As for our colonel, he did go up to Herat. He thanked every person who’d worked on our medevac. He also, quietly, informed his staff that anytime his troops had to call in an ISAF medevac, they were to also begin arranging an American backup, just in case. He understood that demeaning them would do no good; rather, he continued to encourage their participation and use them as a resource when he could, but also made contingency plans with U.S. forces. It proved to be an effective strategy for a commander. It might also be a more effective strategy for a president.