The first Dutchman to reside in the highest office in the then Paris-based NATO-headquarters was Dirk Stikker (1897-1979). He started his professional career managing Dutch multinational Heineken, but went into politics after the devastating Second World War as co-founder of the Dutch liberal party VVD. During his stint as minister of Foreign Affairs – from 1948 to 1951 – he was one of the negotiators and signatories of the North Atlantic Treaty.

Stikker was the Dutch Permanent Representative to NATO when, in 1961, he was asked to succeed the Belgian secretary-general Paul-Henri Spaak. Stikker found a full desk with the failed Bay of Pigs Invasion, a festering crisis between NATO allies Greece and Turkey over Cyprus, and of course the tempestuous Soviet leader Nikita Khrushchev. During Stikker’s tenure as secretary-general the Berlin Wall was built and the world was at the brink of war during the Cuban Missile Crisis.

Stikker – who in addition to his native Dutch was fluent in English, French and German – brought his business-like pragmatic demeanour to NATO and tried to keep meetings to the point and preferably confined to military instead of political issues. Nevertheless, he made long hours during the first half of his term. In his autobiography Stikker mentions a ‘normal’ workweek of fourteen hours a day, seven days a week. ‘But we steadfast people from Groningen don’t shy away from a 100-hour workweek’. Unfortunately we don’t know what his wife and kids thought of the fact that the secretary-general was married to his job.

Stikker didn’t seek the spotlights as secretary-general. Instead he preferred quietly exercising power from the sidelines, trying to build bridges. That wasn’t easy. As a staunch Atlanticist Stikker built up a warm relationship with the American president John F. Kennedy. But French president Charles De Gaulle thought the Dutchman was too sympathetic to the American view and stubbornly refused to receive the secretary-general, in spite of Stikker’s efforts to maintain a working relationship.

Unbeknownst to the general public, frail health was Stikker’s prime reason for preferring written communication and shying from media appearances. His work ethos came back to haunt him. In 1962 Kennedy personally sent Air Force One to collect Stikker for cancer treatment in Washington. The international agenda didn’t allow a lot of time for recovery. During the second half of his term health concerns strongly hampered Stikker and in 1964 he decided to resign as secretary-general.

Luns served as secretary general of NATO for thirteen years, setting a record unbroken to this date. He was a true career diplomat who’d also served as minister of Foreign Affairs for nearly fifteen years before making the transfer to NATO in 1971. Luns was downright relieved to leave The Hague for Brussels. As a conservative Realpolitiker his views were increasingly questioned in the then left-leaning Netherlands.

His strong pro-American position was appreciated more in the NATO HQ, although discussions sometimes became confrontational if Luns sensed someone did not think NATO was fundamental for transatlantic security. The secretary general simply expected everyone to be on board with his devoted Atlanticism.

On the whole however, Luns chaired meetings with a sense of humour and rather informally. He called ambassadors by their first name and put on slippers during lengthy North Atlantic Council discussions. Luns relied on his knowledge and charisma to foster consensus.

There was a lot to discuss. The first decade of his tenure was dominated by détente and arms controls talks between the United States and the Soviet Union. In vain, Luns tried to urge the allies to invest more in defence. This changed from 1979 onwards when the Cold War heated up with the Soviet invasion of Afghanistan and president Ronald Reagan’s confrontational stance vis-à-vis the ‘Evil Empire’.

Although his panache was not very Dutch, Luns was a true Dutchman in other respects. He strictly kept to office hours, working nine to five unless a very important meeting was scheduled. Also, while advocating defence spending, Luns himself was quite frugal. His preference for repaired clothes made him look dishevelled at times, much to the dismay of Mrs. Luns. Some critics believed Luns’s effective leadership was hampered by the fact that he stayed in NATO’s top position too long. But his commitment to transatlantic cooperation was undeniably unwavering. Luns stayed in Brussels after resigning as secretary-general in 1984.

The next Dutchman to lead NATO entered office twenty years after Luns left. Jaap de Hoop Scheffer was secretary-general from 2004 to 2009, a transitional period for the alliance that brought a significant expansion in size and scope. During his time in office NATO welcomed no less than nine new member states and was involved in out-of-area operations in Afghanistan, the Indian Ocean and Africa.

The position of NATO secretary general was the culmination of De Hoop Scheffer’s long career as a diplomat and politician. He served as a parliamentarian for the Dutch Christian-Democrats (CDA) for sixteen years, moving to Brussels after a two-year stint as minister of Foreign Affairs.

De Hoop Scheffer was an accessible secretary general who made an effort of wide-ranging public diplomacy efforts. During his time in office he made full use of the fact he is fluent in both English and French, the two official NATO languages. His sporting activities – especially running and mountain biking – proved a challenge for his security team, but the resulting stamina came in very handy for ‘on the go’ diplomacy during a biking tour organized by president George Bush around his Texan ranch.

Bush’s foreign policy also proved challenging. When De Hoop Scheffer started out as secretary general the alliance was torn, in particular by the war in Iraq. He took up the role of conciliator, using his valued skills as a listener to forge a new consensus and usher in a period of calm. De Hoop Scheffer methodically chaired Council meetings, making sure all allies were heard and assiduously deliberating each issue. According to critics De Hoop Scheffer perhaps treaded too carefully and shied away from taking a political stance, but he did succeed in papering over the differences. This is perhaps symbolized best by the full return of France into the fold, traditionally the most vocal critic of American policy.

While NATO expanded its presence across the globe, dark clouds gathered on the horizon. After the seemingly unipolar nineties NATO came to the realization it couldn’t unilaterally claim a monopoly on peace and security. De Hoop Scheffer proved prescient when he proclaimed the major geopolitical players of the 21st century would be the US, the EU, China and the other BRICS members.

A resentful Russia made itself known. Former Warsaw Pact members were integrated into NATO while trying to avoid offending the Kremlin, but during De Hoop Scheffer’s tenure as secretary-general Russian president Vladimir Putin became more and more vocal in his critique of NATO. Georgian membership aspirations even prompted an invasion, presaging things to come.

Since last year NATO has a Dutch secretary-general again. Mark Rutte is cut for the job, a staunch Atlanticist like his three predecessors. Wake him up in the middle of the night and he will tell you NATO is the cornerstone of European security. That security, core business of the alliance, has not been at such risk in decades as it has been since Russia’s large-scale invasion of Ukraine. The soul searching from the De Hoop Scheffer years is definitely over: arch-rival Russia is back with a vengeance.

Rutte has extensive international experience, being at the forefront of European politics for almost fourteen years as the longest serving prime minister in Dutch history. He himself was trained as a historian. Rutte was politically active in the liberal VVD since the late eighties, trading in his job as a manager for Unilever for a cabinet position in 2002, leading his party from 2006 onward. He served as prime minister since 2010 before leaving the ‘Torentje’ (little tower) office in The Hague for the NATO HQ in Brussels.

The Dutch were used to Rutte’s jovial modus operandi, but it was a breath of fresh air in the hallowed halls of NATO. During his first weeks in office he talked with everyone, including the interns. Rutte – like his fellow Dutchmen back home – is averse to hierarchy and will stand in line for his cup of coffee just as everyone else. He doesn’t live in the opulent official residence, but rents his own place. Rutte did have to change one thing though: he was famed for cycling to his office as prime minister, but is now driven as secretary general.

Rutte is aiming for an informal vibe, but wants more substantive meetings too. As chair he doesn’t simply go through the motions but asks sharp questions. The secretary general constantly keeps close tabs on all allies, immediately making phone calls when he senses something’s awry. He honed his bridge building skills heading complicated coalition governments in the Netherlands.

Things might have become more relaxed in the NATO offices, but there’s also enough to worry about. In his first major speech Rutte warned the general public the alliance is ‘not yet at war but definitely no longer at peace.’ And Russian and also Chinese ambitions are one thing, but maybe Rutte’s biggest challenge lies inside. Rutte also got the job because of his reputation as ‘Trump-whisperer’. Keeping everybody in line, including the capricious American president will be a delicate balancing act. In the coming years, Rutte will quite often have to find a creative way out of difficult situations.