You could almost say that the only thing John Key was good at was winning elections. As if that were a small talent for a politician.

He was very good at that, anyway. Leading his party in successive elections to a share of 44%, 47% and 47% again of the vote is a truly remarkable achievement in a proportional multi-party system. Helen Clark, the three-term prime minister he defeated to get the job in 2008, never managed more than 41%. Yet in her case you could readily point to several political accomplishments which could be variously described as being part of her legacy, mostly in the form of new social welfare entitlements such as the Working for Families scheme, or social security instruments such as KiwiSaver and the Cullen Fund.

After 15 years of radical neoliberal reforms, Clark applied the brakes, while leaving the core of those reforms untouched. She stopped the privatisation of the government workplace insurer, ACC. She abolished market rents for state housing. Through those measures and others like them, she reoriented the political centre. You could call the new consensus ‘neoliberalism with a human face’. It operated through a state that appeared to look after its citizens, while doing nothing to reverse the extraordinary levels of social inequality produced under successive governments.

John Key took that consensus and walked away with it. Clark’s reformist momentum had simply stalled. Her political project had nowhere else to go, and needed to be going somewhere in order to justify itself. It was like when Hillary Clinton tried to replicate Obama’s campaign but without being able to run as the candidate of change.

In specular fashion, Key offered instead a paradoxical continuity: putting the Tories in charge of Labour’s house, and making them the custodians of Clark’s achievements. Not a new thing in the country’s political history, but done so well that the public barely noticed. It was not so much an election as a wonderfully executed burglary.

Eight years later, just as he appeared poised to sleepwalk into a fourth term, Key walked away this morning. He will be in charge of the country for one more week only.

Historians will remember him. But for what? Always he did so little. Having gone into power just as the global financial crisis kicked into gear, he passed up on the opportunity to respond with a program of outright austerity.

He cut public sector jobs, which is hardly ever an unpopular move. He enacted welfare reforms that introduced social controls rather than slashing entitlements, so that affected people would be blamed for falling out of the net themselves, rather than being pushed. He deprived sectors of the state of funding often just by failing to increase it to keep up with costs. (The state public radio, for instance, has had its funding frozen since he took office.) He privatised state energy companies, but only up to 49% of the shares – possibly the most emblematic example of his pragmatism.

He championed the TPP, but without ever letting us forget that it was the brainchild of a Labour foreign minister. He brought into his coalition the Māori Party, the product of a split with Labour during the Clark years, without making undue concessions to its demands. He eschewed the racially divisive platform of his predecessor, Don Brash, proving more successful at settling claims under the Treaty of Waitangi than Clark.

Throughout it all, he kept a constant eye on the dial of that consensus, without ever attempting to shift it. He was helped in this by his faithful pollster, later to be included in the cast of characters of journalist Nicky Hager’s book Dirty Politics. Ultimately, the accusation that the prime minister was running a Nixonesque ‘ratfucking’ operation against the Labour Party and other political adversaries out of his office didn’t stick. I suspect historians will look into that again, too. The case is hardly a weak one, especially since the weeks following the publication of the book were marked by one of his aides taking a sudden and highly convenient holiday.

When I say that Key was supremely good at winning elections, I don’t mean to say that we should forget or excuse some of the methods he employed to this end. But neither should we overestimate their effect. By far Key’s greatest single achievement was to position himself as the natural choice for continuity of government from the Clark years and into an indefinite future of modest, unambitious prosperity (‘we’re on the cusp of something special’, he famously read once off a Crosby-Textor cue card). His was an electoral consensus built on a bulging centre comprising affluent and semi-affluent voters, who either own property or are heavily mortgaged, while the large and growing ranks of the working poor and the destitute have stopped voting altogether and may never become a constituency again. Under these social conditions, the John Key project was virtually doomed to succeed, as it effectively deprived Labour and the Greens of people to appeal to. Absent an economic crisis, the centre-left has no intervention to offer, nor solutions to problems that largely affect a non-voting public.

But it would be foolish to underestimate the role of Key’s personal appeal in all this. For eight years he played the part of the prime minister beautifully. He was a reassuring presence, projecting confidence and competence yet never appearing to take himself or his office too seriously. Neither the media nor the opposition managed to alter those perceptions in relation to such issues as his handling of the housing crisis, or the reconstruction of Christchurch. He was the prime minister of those who think that the country almost governs itself, and that we shouldn’t upset its balance. But that act won’t be an easy one to follow for his colleagues: he struck that tone effortlessly with his public persona, and it gave credibility to the very idea of his government. Someone will have to replicate that.

Yet in spite of his great talent for winning elections – or maybe because of it – John Key has no legacy. Called upon to account for his achievements after today’s surprise announcement, the New Zealand’s Herald was barely able to compose four short paragraphs, including some questionable entries (‘attended the Queen’s residence at Balmoral’, ‘aimed to establish the Trans-Pacific Partnership’ – but failed). The one time he tried to use his office to promote lasting change, through a referendum to adopt a new national flag, it starkly exposed his lack of political substance and vision. Everyone quickly recognised it as the branding exercise that it was, and on this occasion the great communicator failed to persuade the public that the idea had any merit. It was a symbolic issue, yes. But it makes the misstep even more telling for a politician who relied so heavily on his image.

That the country governs itself is, of course, an illusion. The auto-pilot set by Helen Clark was never meant to take us this far, and the many structural issues of the New Zealand economy could yet come to a head all at once. When that happens, we may look quite differently at John Key’s absent legacy.