General Dwight Eisenhower, left, and General Sir Bernard L. Montgomery often clashed, but that didn't affect the larger U.S.-U.K. relationship.Associated Press

In the study at the ambassador’s residence of the British embassy sits a watercolor portrait of Field Marshal Bernard Law Montgomery, 1st Viscount Montgomery of Alamein.

Montgomery commanded the Allied ground forces during Operation Overlord, from the initial landings on D-Day through the Battle of Normandy, working closely with his American counterparts. His portrait might seem a tribute to smooth, amicable cooperation between the U.S. and the U.K.

Yet the actual relationship between Montgomery and General Dwight Eisenhower, the Supreme Allied Commander, was often difficult and always tumultuous. They got off to a rocky start in their first meeting in 1942, when Monty reprimanded Ike for smoking, then loudly told a colleague in the room, “Ike’s a nice chap. No soldier, though.” The tensions persisted through the next three years, on and off the battlefield. At one point, Monty’s pursuit of his own plan for Normandy led Eisenhower to seriously consider sacking him.

But he didn’t. Despite the clashes, Ike recognized Monty’s qualities as a soldier, but more important, he understood that dismissing him would have provoked a huge political backlash in Britain at a crucial moment in the war.

Ike understood that the relationship had to be steadfast, that it had to transcend personality clashes or political bumps along the way. It had to be bigger than that.

The artist who painted the watercolor of Montgomery understood this clearly. He left an inscription on the back: “To Monty, from your friend Ike. 1952.”

I’d barely unpacked my bags three and a half years ago in the beautiful Queen Anne mansion that is home to the U.K. ambassador in Washington when I was handed an article predicting the imminent demise of the partnership between the United States and Britain. I was given another such story today.

And I’m willing to bet that every one of the 23 ambassadors who unpacked their bags in the century before me had the same sort of article periodically delivered to them.

The stories always suggest that the U.K. no longer matters to the U.S., and that some other nation—Germany, or France, or whoever—is America’s new best friend.

And our response, every time, has been the same: to carry on with the day-to-day work of two countries united by shared goals, common values, and the tight ties between everyday Britons and Americans. It’s exactly what we’ve done since long before Winston Churchill coined the phrase special relationship in his Iron Curtain speech in Fulton, Missouri, in 1946.

There has not been a single time since I took office when either I or my staff hasn’t been able to secure support, counsel, or advice from one of our U.S. counterparts—from the grass roots to the top of the administration. When we’ve needed help, it’s been given. Whenever we’ve asked for a phone call with the president, it’s been given priority.

Cabinet secretaries are regularly at the British residence, and our ministers and secretaries of state visit their U.S. counterparts frequently. The president’s relationship with Prime Minister Theresa May—contrary to some reports—is also excellent. It is respectful, and on important issues, there is free, open dialogue.

Earlier this month, Secretary of State Mike Pompeo told Foreign Secretary Jeremy Hunt in London that the special relationship “doesn’t simply endure,” but “thrives.” He added later: “Our partnership allows us to protect the values we hold dear and to stand together to address the challenges of our time—China, Russia, Iran, the Middle East … We must tend to it, we must expand it, and we must not forget how special it really is.”

This isn’t politician-speak—this is what I see every day. So when I pick up these gloomy articles, it’s with a wry smile and slight exasperation that I wish the authors could see it too.

I was national security adviser for four years in the British government before coming to D.C. I knew then that U.K.-U.S. defense cooperation forms the broadest, deepest, and most advanced partnership any two countries enjoy. We’re close allies in NATO, permanent members of the UN Security Council, and leading nuclear powers—our cooperation is vital to international peace and security. We are the U.S.’s only “Day One, Night One” partner, deployed around the globe and capable of operating from the outset of high-intensity conflicts.

But working here now, I see it unfolding on the ground. Our forces are deliberately designed to operate seamlessly alongside American troops. We not only fight together, but train together. We have 1,200 British servicemen and servicewomen embedded with the U.S. armed forces, in 30 states across America. A map above my desk has dozens and dozens of tiny pins in it—their primary-colored heads create a haphazard rainbow of dots. It paints, for me, a very clear visual of decades of vital partnership.

A few months ago, I stood on the deck of the 65,000-ton aircraft carrier HMS Queen Elizabeth II—the largest warship ever built for the Royal Navy—as it came alongside the pier in New York Harbor. A few days before, it had been used for test flights of the F-35B short take-off and vertical-landing fighters created out of the U.K.-U.S.-supported Joint Strike Fighter program, which are now the backbone of Britain’s war-fighting capability. By 2021, the U.S. Marine Corps will operate its own F-35B jets in tandem with squadrons from the Royal Navy and the Royal Air Force. And soon the next generation of Columbia and Dreadnought nuclear submarines, which we are building together, will be on patrol in the seas below, underpinning NATO’s collective deterrence.

In its social-media posts, the British Army uses the hashtag #sidebyside. It’s a phrase that was originally used in Churchill’s address to Congress in 1943—“We will wage that war side by side with you … while there is breath in our bodies and while blood flows in our veins”—and neatly summarizes the reciprocal relationship we still enjoy today.

And we were never more grateful for that than on one quiet day in the historic market city of Salisbury in Southwest England when Russian agents used a nerve agent, for the first time in Europe since the Second World War, to attack a man and his daughter.

The country was in shock. In the hours and days that followed, our embassy team and I personally lobbied colleagues in the White House and the State Department for a strong American response—knowing that the U.S. decision would set the standard for Europe and the rest of the world.

And the U.S. delivered. A total of 60 Russian diplomats were expelled from the U.S. Europe then expelled another 60, delivering a blow to the Russian intelligence machine. It’s just one of the countless examples of how the U.S.-U.K. relationship is built not on misty-eyed nostalgia, but on practical, unwavering partnership.

That partnership is also built on global diplomatic influence. The U.K. has one of the largest diplomatic footprints of any country, with embassies and missions around the world. This reach is hugely valuable—and the Americans recognize this. The U.S. has no diplomatic presence in Pyongyang or Tehran. We have had ambassadors and teams in North Korea since the early 2000s and in Iran since 1821. The United States relies on us to be its eyes and ears in places where it has none.

The constant engagement between our Foreign and Commonwealth Office and the U.S. State Department fills my days and weeks in a way that nothing else does.

A British colleague of mine at our embassy in Washington recently told me a story. Her son died suddenly, at age 13, while she and her husband—a British Army colonel—were stationed at Fort Leavenworth in Kansas. He was teaching American (and international) officers national-security and defense policy.

In the unimaginable horror of dealing with all that entailed—the shock, the emotion, the administration, the bureaucracy, the shielding of her two other boys—she found a handwritten note on their doorstep:

“Your loss is our loss. History brought us together—our friendship and our enduring alliance is what will keep us together. Therefore, when we serve together, we grieve together.”

The American woman who had fixed the note on top of a warm meatloaf was not someone my colleague knew particularly well—she worked in a store on the base—but her grandfather had served in World War II. As he was taken to a field hospital in France, he dealt with his unimaginable horror, but with a British corporal by his side. That corporal took the name of the dying man’s mother, and some months later wrote a moving letter to her, paying tribute to her son.

The lady in the store at Fort Leavenworth still had that letter. It was what had moved her to walk along the Missouri River as the sun rose on that August morning to give comfort to the grieving family.

These are the moments I think about when I read another commentary on the special relationship written from a desk in a faraway city.

One of the most important things I’ve learned in my three years here is that we share so much more than relations between diplomats, politicians, and heads of state. The special relationship is about people. Americans and Britons share not only values, but also language, culture, movies, music, and an unwavering belief about what is right and wrong.

It’s a relationship that starts with the personal and reaches the powerful—and that’s why it will always survive.

When the somber, silent procession of former President George H. W. Bush’s funeral passed by our embassy on its way to the National Cathedral just before Christmas, former President George W. Bush leaned across from his far-side seat in one of the cars and saluted the members of the British military who had formed an impromptu honor guard outside the residence gates.

After the long, winding cortege moved slowly up Massachusetts Avenue, one of the D.C. police officers who had been lining the route turned to a member of our staff. “I honestly don’t think there’s a president who wouldn’t have reacted that way,” he told her. “Who could drive by here, look past Churchill’s statue, through those gates, and not think about everything that’s been done by both of us together?”

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