Back in early 2013, when Tony Abbott was leading a highly effective campaign against the Gillard government, Coalition MPs frequently stood up in question time to decry the “worst government ever”.

That term will now come back to haunt the core of Abbott’s supporters in the Liberal Party.

Writing for a News Corp publication at that time, I explained why the term was a gross exaggeration.

The irony is that the term coined by sloganeers at the heart of the Abbott government is likely to be turned by historians on the Abbott-Hockey government itself.

• How the leadership challenge unfolded

• Turbull’s first words after taking the leadership

• Australia’s musical chairs of political leadership

• The economic challenges Turnbull could inherit

Abbott served as Prime Minister for less time that Gillard; passed a lot less legislation than Gillard even on a pro-rata basis; and failed to pass key reforms.

It was a government that could not shake off the spin, oversimplifications and slogans that had served it so well in opposition.

It was a government that stuck to idealistic economic theory when pragmatism was called for to deal with the end of the historic mining boom.

Real disposable incomes were tracking down, unemployment tracking up, business investment paralysed and confidence battered to depressing lows by an ideologically motived policy agenda that did not take the Australian people with it.

And it was a government that insulted Australia’s intelligence.

When Malcolm Turnbull announced his challenge early on Monday morning, he accused Abbott of leading by “slogans and captain’s calls”. Abbott’s response? To send out ministers to say they’d “stopped the boats”.

Turnbull said the Abbott leadership team wasn’t capable of managing the economy – so he sent Treasurer Hockey out to boast that 300,000 jobs had been created in two years.

Did Hockey even know that just to keep up with population growth, 347,000 jobs would need to have been created?

The historic party-room vote on Monday evening is the end of a long experiment launched by Howard-era finance minister Nick Minchin, who rallied right-leaning MPs to oust Turnbull in December 2009.

As political historian Paul Kelly has explained, that move was not only about Minchin’s disgust at the progressive position Turnbull took on climate change action – with Kevin Rudd, Turnbull was seeking to pass the bi-partisan carbon pollution reduction scheme (CPRS).

Kelly argues, quite rightly, that Minchin was ousting Turnbull to prevent a fatal split in the Liberal Party, not unlike the historic split the Labor Party went through in the 1950s.

Be that as it may, the Minchin plan put a hard-right leadership team in place that ultimately failed to take the Australian people with it.

The party’s ruthless attacks on Labor won it power, but it then sought to goad Australian voters into accepting policies that they had not voted for, and that were motivated by neo-liberal economic theories that they didn’t accept.

Instead of explaining how they could get what they wanted in healthcare, education, aged care and a raft of other areas, the government expended valuable political capital trying to say “you can’t have them”. Persistently poor opinion polls were the result.

When Malcolm Turnbull stepped up before tired journalists in the Blue Room late on Monday night, he looked as tired as many of us felt. His victory speech was less than inspiring.

However Turnbull had used his best passion, energy, and formidable rhetorical skills in announcing the challenge on Monday morning.

It was at that earlier press conference that Turnbull looked like a straight-shooting reformer that might surpass the reform era achievement’s of Labor’s Bob Hawke.

Australians of all political stripes should hope that he is.

On Monday night he was right to argue that they is plenty of talent within the Liberal ranks. And he promised to lead a “truly Liberal” government, with respect for “freedom, the individual and markets”, to create an economy that was “agile and innovative”.

Deputy leader Julie Bishop praised the “Menzien values and beliefs” that would guide their leadership.

It is sad to say, but these will largely be new directions for a party that had strayed too far from the vision of founder Robert Menzies.

And those new directions are urgently needed. The hour is late for the genuine reforms needed to return Australia to prosperity in a global economy markedly different from the conditions that prevailed when Abbott took the leadership in 2009.

The 14th of September 2015 will be a sad day for many – a day on which the Abbott experiment was finally revealed as a costly mistake for the nation.

Was it the worst government ever? Well, they said it.