JACINDA Ardern’s announcement last Thursday that she will resign as New Zealand’s Prime Minister and leader of the New Zealand Labour Party came as a shock to outside observers.

Holding back tears, she explained that after much soul-searching, she felt she no longer had the energy or motivation to do her role justice. By stepping down, she has allowed her party to find a new leader in Chris Hipkins, who can now establish himself as Prime Minister ahead of a general election in October this year.

The shock came not because there were strong expectations that an Ardern-led Labour Party would win that contest but because, despite their deteriorating polling, we are not used to seeing politicians decide to give it all up.

We have plenty of examples of national leaders in British politics who refused to go until they were forced out of office. It took a historic 54 government resignations in three days for Boris Johnson to finally resign after months of contestation over his position and collapsing poll numbers for him and his party.

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Margaret Thatcher only stood down when a succession of her Cabinet Secretaries demanded that she do so. John Major clung on until ousted by Tony Blair despite it being evident that he was done by 1995.

Alex Salmond reportedly only resigned in 2014 because he was under the impression that Nicola Sturgeon would flounder and his party would welcome him back with open arms. When that didn’t happen, he tried to revive his career through the Alba Party, which managed under two per cent of the vote at the 2021 Scottish Parliament elections while aggravating factionalism within the Scottish independence movement.

David Cameron left because he knew that post-Brexit referendum, he couldn’t control his parliamentary party and did not want to be held responsible for the undignified mess that would follow. Theresa May discovered that he was right about that.

How often do we see a national leader depart entirely of their own volition, free of a killer scandal, the withdrawn confidence of their colleagues, or a vote against them by the public?

When we look across the world at the broad swathe of political leaders, they tend to be united by a tendency to hold on to power too long rather than leaving at the right moment – or earlier than they could have.

Some argue that Ardern has resigned because she sees the writing on the wall in the form of her party’s polling and her country’s dire economic prospects.

I think this does her a disservice. Ardern could push ahead if she wants. In the final poll of 2022, her ratings slightly outdid her party’s. She was comfortably the leader voters were most likely to say they wanted as Prime Minister and had the highest net favourability rating of any party leader – holding a substantial 30-point lead over her closest rival.

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Take any of the leaders I have mentioned and put them in Ardern’s position, and what would they do? I would bet my pension that almost all of them would run for re-election. Many national leaders who have led their parties to defeat would have killed for Ardern’s ratings at this point in the election cycle.

National political leaders get to their positions because they have an array of the right talents and skills and a healthy dose of luck. But they also have something else that gets them through the long years of ineffectual political opposition, the freezing cold and hammering rain on the voters’ doorsteps, the repressive scrutiny and the glare of the studio lights: the will to power.

And that is not necessarily a bad thing. Not all politics is ego. Political power and the will to possess it are not inherent evils – the leaders of the Attlee government undoubtedly had strong wills to power, acquired it, and channelled it into the creation of the post-war welfare state and the founding of the National Health Service.

Where the will to power becomes poisonous is when it manifests as a will to power for power’s sake. The writing was on the wall for Boris Johnson months before he resigned, and his party tore itself apart over the course of those months. Voter’s perceptions of Johnson and his party eroded rapidly, and potential replacements became toxic to much of the Conservative membership because they called on Johnson to go.

His party management, including freezing out political threats to his leadership and casting them as the enemy within, created conditions in which ill-suited and ill-talented ideological purists were best poised to succeed him. When they did, they wreaked havoc on the country.

In contrast, Ardern has allowed her party to refresh itself through new leadership. Only one candidate was nominated, meaning the New Zealand Labour Party found a new leader within days. That leader now has greater freedom of action to depart from Ardern-era policies and outline a new programme to tackle the country's challenges.

They may still lose and are unlikely to win a majority. But suppose Labour does win the most seats. In that case, the opposition will not have to either work with a leader they have demonised for years or cobble together a potentially unstable and ad hoc arrangement to govern.

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By resigning now, she gives her party and country the best chance for democratic renewal without damaging political instability in the aftermath, which is crucial amid the current economic crisis.

Among the many lessons of the past decade of British politics is that how a national leader’s career ends matters as much as how it was conducted. They can allow the will to power to become toxic, poisoning their legacy and hindering their successors. Or they can think strategically, demonstrate self-knowledge, and choose the right time to go.

All political careers end, including those that reach the pinnacle of political power. We would all be better off with more Arderns, who choose their end, and fewer Johnsons, who must have the end thrust upon them.