This lack of freshness is exacerbated by the leadership characteristics of Malcolm Turnbull, Bill Shorten and those around them as we face the possibility of a second, successive election pitting these two men against each other. Turnbull promised a fresh approach when he took office from Tony Abbott in 2015 but has been either ground down by the system, greatly overrated or both. Australian political leadership looks old and grey, though neither leader is particularly old by historic standards. Shorten is only 50.

Yet around the world, the picture is very different. Nation after nation is experimenting with new leaders, often very young ones, and sometimes even new parties. That is the case in France, Austria, Canada and New Zealand, not to mention old Donald Trump's United States. The picture is not uniform because Angela Merkel held on for a remarkable fourth term in Germany. Theresa May, although a newcomer, is struggling in Britain. But figures like Justin Trudeau in Canada, Emmanuel Macron in France, and now 31-year-old wunderkind Sebastian Kurz in Austria and Jacinda Ardern in New Zealand are fresh faces.

Against this international background, New Zealand is the most obvious comparison. As Australia shuffles aimlessly towards the next election, invigoration of our political system is nowhere in sight. More young leaders might not be the whole answer and I am not starry-eyed enough to believe that youth always equals wisdom and virtue. But youth can bring freshness and with that can come improvement if there is a willingness to break out of partisan deadlock.

Ardern's ascension to her country's leadership exhibited several factors. She is very young, though already a seasoned political professional. Just 37 years old, she is a decade younger than the young premiers of NSW and Queensland, Gladys Berejiklian and Annastacia Palaszczuk, and about 25 years younger than Turnbull and Julie Bishop, who are in their sixties.

Ardern took over her party's leadership in a bloodless transition when the previous New Zealand Labour leader, Andrew Little, stepped down less than two months before the election. At that time, NZ Labour was trailing badly in the polls and given little chance of winning. Ardern reinvigorated her party, though many thought it had fallen short at the election.

There are many differences between New Zealand and Australian politics, including the electoral system and aspects of its party system. But there are still lessons for Australia. Ardern's rise showed that leadership changes can be made very late in the electoral cycle and still make a difference.

The obvious Australian similarity was when Bob Hawke replaced Bill Hayden in February 1983, on the day the election was called. Hawke went on to defeat Malcolm Fraser. Hayden would probably have won that election anyway but the outcome looked close enough that there was doubt in Labor power brokers' minds about whether to support Hawke's coup.

There are some unexpected personal similarities between Hawke and Ardern. He was still relatively young, 53 years old when he became prime minister, and he brought with him a similar energy and freshness. He had much less parliamentary experience but was a seasoned union leader and public performer. He, too, had an outgoing personality and gave every indication of enjoying, even seeking, the limelight.

The Hawke example shows the Australian political system can sometimes act decisively, like the New Zealanders did this time. That being the case, Turnbull cannot rest easy until the election campaign is under way unless he can increase his government's popularity. The option to replace him if he looks like losing remains open until almost the last gasp.

Shorten's case is more complicated given Labor's tighter rules for replacing a parliamentary leader. Even if he looks like losing the next election, it would probably mean him stepping down voluntarily in the interests of the party rather than being forced out. That is unlikely unless he was facing a clear defeat.

The bigger question than whether the political parties would act if pushed is whether Australian politics has the capacity to produce potential young leaders like Ardern, Macron and Trudeau, with the capacity to freshen up our stale political system. They need not be absolute outsiders – none of the above were – indeed, Trudeau's father was prime minister and Macron had important patrons. And youth is not everything, as Bernie Sanders showed.

But they do need to fresh, outgoing personalities to capture popular affection, and fresh ideas to break through policy stalemates. These stalemates produce staleness, which is Australia's problem today.

Neither Turnbull nor Shorten are being pushed hard. Among the obvious candidates to replace them – such as Peter Dutton, Bishop, Anthony Albanese or Chris Bowen – there appears to be no one with the characteristics we see in these new young leaders around the world. Rather, they all seem to be battle-hardened party warriors whose efforts are more dedicated to convincing their colleagues than to connecting with the people. Our future seems more likely to be business as usual than youthful reinvigoration.

John Warhurst is an emeritus professor of political science at the Australian National University.