In search of a quote the other day, I rang up a contact who can normally be relied upon to deliver a near perfect sound-bite, with the requisite servings of knowledge, erudition and controversy. Alas, this time he could not help, because he is hoping to win pre-selection as a parliamentary candidate and thought it better to refrain from public comment.

The conversation then turned to his prospects for being chosen as the candidate to fight the seat, which he did not think were good. The problem, he confided, was that he is not a professional politician, and he would be handicapped by having conducted most of his adult life outside of the realm of politics.

The professionalisation of politics is much in the news, both here in Australia and at home in Britain: this modern-day tendency for public life to be dominated by those who have essentially lived a political life.

Australia throws up numerous examples. Kevin Rudd spent seven years as a career diplomat, but has been directly involved in politics for 22 years, having started out as the chief of staff for the then opposition leader in Queensland in 1988. His deputy, Julia Gillard, started out as a lawyer, but also left to become the chief of staff for the then opposition leader in Victoria. After turning his back on the priesthood, Tony Abbott worked for a time as a journalist before becoming the press secretary to the then Liberal leader, John Hewson. He has remained in politics pretty much ever since.

This trio is presently dominating Australian politics, and in a neat piece of political asymmetry, two well-known figures who boasted high-profile outside careers before entering politics have seen their political fortunes dip. The former opposition leader, Malcolm Turnbull, a highly remunerated former lawyer and businessman, recently announced he was stepping down at the next election, only to reverse himself a few weeks later. Then, there is the little-seen environment minister Peter Garrett, the former lead singer of Midnight Oil, who has been sidelined following the home insulation mess.

A few weeks back, the former Treasurer, Peter Costello, weighed into the debate by arguing that it pays to get into professional politics early, a jibe at Malcolm Turnbull, whose skills set appeared to malfunction in Canberra. "I do not think a person's pre-parliamentary career counts one way or another," said Costello. "But I do think that to be successful in politics a person needs to pick it up early." That would appear to disqualify people who want to see their careers come to fruition before considering entering politics.

"A successful businessman has likely spent a long part of his working life outside politics," said Mr Costello. "It's harder to adjust to parliamentary life at 50 than it is at 30. The number of people who enter politics later - from whatever occupation - and go on to have successful careers as senior ministers is tiny."

The alternative view, of course, is that the political late-bloomers bring with them a wealth of experience and expertise. And perhaps they are not so prone to become as narrowly and destructively partisan as professional politicians, for whom politics infuses everything.

As in Britain and America, Australian politics now has the feel and urgency of a permanent campaign, a battle for favourable headlines the next day rather than a battle of ideas which shape the long-term future. Many believe this is a by-product of the proliferation of political professionals, who know little else but politics.

Of course, career politicians are hardly new on the scene. As the veteran Canberra watcher Mungo MacCullum recently observed in The Monthly, the three Prime Ministers who have dominated the past three decades, Bob Hawke, Paul Keating and John Howard, all started young. He also notes: "In the past 20 years alone, the Liberal Party has embraced John Hewson and Malcolm Turnbull, both outstanding figures in the commercial world, both political disasters."

But would not Australia's increasingly professional political class occasionally benefit from the addition of a few talented amateurs?

