In 2005 John Howard had been prime minister for nearly a decade and didn't look particularly vulnerable. But then he decided to ramp up Australia's migration intake. Net overseas migration jumped from the 100,000 it had been in 2004 to over 200,000 in just a couple of years.

In 2005 migration overtook natural increase as the dominant driver of population growth, and we entered an era of rapid population growth, which we are still in. Our population now increases by a million people every three years.

The era of rapid population growth has also been one of great political instability. John Howard lost the 2007 election and indeed lost his own seat. His successor, Kevin Rudd, maintained and even increased net migration. When he was questioned about rapid population growth in 2009 he declared he was in favour of a Big Australia. His personal approval ratings had been high until that time, but then they started to fall. He was replaced by Julia Gillard in 2010.

Julia Gillard was aware of the damage that Big Australia had done to Kevin Rudd, and said she was not in favour of Big Australia. But she did not change the migration intake much and the problems of rapid population growth persisted. She was replaced by Kevin Rudd in 2013, and he in turn lost the 2013 election and the Liberal Party came to power with Tony Abbott as Prime Minister. Tony Abbott maintained Australia's net migration intake at over 200,000 per annum, and rapid population growth continued.

Now just two years later Tony Abbott has been replaced by Malcolm Turnbull. Australia has been described as the democratic coup capital of the world, and our political instability has been the subject of international comment. Now of course there are many factors at work in every political setting. I acknowledge the role of WorkChoices in the demise of John Howard. I acknowledge the role of internal undermining and the difficulties of managing the hung parliament in the demise of Julia Gillard. I think that Tony Abbott made a Faustian deal with the devil by promising that there would be no cuts to health, education or pensions when he was opposition leader, only to renege on these promises in the 2014 Budget.

But those factors are insufficient to explain the political instability of the past decade, especially when you see it going on at a state level too. In Victoria and Queensland we have seen right wing governments elected then defeated after just one term, with the elected Victorian premier toppled in his first term by his own party, just as happened to Kevin Rudd and as has just happened to Tony Abbott.

In 2011 I gave a speech which I called the Witches’ Hats Theory of Government. Having studied a lot of countries around the world, I had come to the conclusion that countries with large and rapidly growing populations had more political instability than countries with small and relatively stable populations. I compared governing a country, with various public policy problems you have to solve, to an advanced driving course where you have to navigate a road without knocking over strategically placed orange traffic cones known as witches hats. Each public policy failure – education, unemployment, aged care, planning, represents a witches hat knocked over.

If you knock over too many witches hats, you fail the test, that is to say the electorate, or your party, votes you out. I noted back in 2011 that if a country was stable or only growing slowly its leaders seemed to have fewer problems, and more time to solve the problems, a more content population, and much better political longevity.

But if a country was growing rapidly, problems such as traffic congestion, housing affordability, planning disputes and infrastructure shortfalls generated political instability. It is like driving the car at great speed. Inevitably you are going to hit more hats. Infrastructure is a particular difficulty. A country or community growing at 2% has double the infrastructure task of a stable community, which is why pensioners and retirees feel particularly under the pump from utility charges in a rapidly growing population.

The Abbott Government had little support from young people, who are the victims of job insecurity, housing unaffordability and rising student debt. All of these things were made worse by rapid population growth. When the jobs at 7-Eleven and numerous other retail outlets are all going to easily exploit temporary migrant workers, how are young Australians supposed to become financially independent and get entry level work experience?

The Abbott Government also lost the support of older people with its broken promises over cuts to education, health and pensions. It was looking to find money to deliver on Mr Abbott's promise to be the infrastructure prime minister, and avoid a witches hat which would not have been there if our population growth had not been so rapid.

So the witches hats have claimed another victim. I offer the same advice to Prime Minister Turnbull and his incoming government as I have freely offered to his predecessors. If you want to last, stop driving so fast!