A relationship of mutual convenience between Prime Minister Malcolm Turnbull and the federal Liberal party is drawing to a close. Each used the other for practical purposes.

Mr Turnbull used the Liberal Party as his vehicle to enter parliamentary politics and become Prime Minister, having earlier tried but failed to win behind-the-scenes preferment for a Labor seat.

The Liberal Party, in turn, used Mr Turnbull to squeeze out another election win in 2016, papering his face over that of his unpopular predecessor, Tony Abbott, who by mid-election cycle had proven a likely electoral loser.

The obvious neediness at the heart of Mr Turnbull's pursuit of power fatally deprived him of the ballast necessary for good judgement and competent leadership. ( ABC News: Jed Cooper )

To become Prime Minister, Mr Turnbull made himself a willing hostage at the outset to right-wing policies that contradicted his political persona.

Early expectations among some that he would use his ascension to drag the federal Coalition towards the centre and some sort of meaningful relationship with the contemporary world gradually expired. Moderate swinging voters became disillusioned.

Mr Abbott's vengeful policy terrorism and Liberal frontbencher Peter Dutton's prime ministerial ambitions, meanwhile, dragged internal Liberal party politics further and further to the extreme.

In choosing to remain hostage to this right-wing lunge in conservative politics in Australia, rather than standing and fighting to move it back to the mainstream, Mr Turnbull erased his moderate face, destroying his only utility — electoral utility — to the Liberals. He wrecked his prime ministership in the process.

Turnbull could have gone either way in politics

Faustian deals sometimes work in politics. This one did not.

Mr Turnbull is one of a small number of prominent Liberals who, early on in their careers, could have gone either way in their party political allegiance. The others are John Hewson, Peter Costello, Brendan Nelson and, incredibly, so it seems now, Tony Abbott.

Each explored or contemplated a Labor path to parliament. Mr Nelson was actually at one time a Labor Party branch member.

Mr Abbott corresponded with his Catholic political mentor, BA Santamaria, openly canvassing both his Labor and Liberal party political options.

Of the five, four became party leaders, and two of those became prime ministers.

Beyond their rather striking success rate in rising to, or near, the top, it is hard to draw conclusions about them as a group.

Tony Abbott is one of a small number of prominent Liberals who could have gone either way in politics, openly canvassing both his Labor and Liberal party options. ( Adam Kennedy: ABC News )

Turnbull has no core set of beliefs

In his no-confidence motion speech against the Prime Minister in Parliament yesterday, Opposition Leader Bill Shorten likened Mr Turnbull to the weak and, by the end, despised early 1970s Liberal prime minister Billy McMahon.

Bill Shorten likened Mr Turnbull to William McMahon, whom history has judged to be a vacuous, dissembling Sydney powermonger. ( ABC News: James Bennett )

And there is something to the comparison. History has judged Mr McMahon a vacuous, dissembling Sydney powermonger.

The crushing contemporary verdict on Mr Turnbull is that he has no core set of beliefs from which to dissemble: just an emptiness that only the prestige of the prime ministership can fulfil.

The obvious neediness at the heart of Mr Turnbull's pursuit of power fatally deprived him of the ballast necessary for good judgement to be exercised and competent leadership to be achieved.

Where the McMahon government parallel is spot on is in relation to the Liberal Party itself. Following the long reign of Sir Robert Menzies, three Liberal prime ministers passed in quick succession: Harold Holt, John Gorton and Mr McMahon. Mr Holt drowned in office; Mr Gorton was ousted from office by the plotting Mr McMahon; and Mr McMahon was pushed from office by a resurgent Labor Party led by Gough Whitlam.

Mr Menzies had hung on too long as prime minister and left no-one in his wake with the authority to hold the Liberals together; open party warfare was the result.

Mr Menzies' modern iteration, John Howard, made the same mistake. The Abbott government, the Turnbull Government and the nascent — and likely short-lived — Dutton government, all operating against the backdrop of intense internal party conflict, is the unhappy result.

This is not just unfortunate for the Liberal Party and its supporters, but also a disaster for Australia, where coherent and comprehensive responses to policy challenges of the utmost seriousness remain unaddressed.

Turnbull's franchise has expired

An early election won't save Malcolm Turnbull. His franchise has expired. The riven state of the Liberal Party makes a Dutton government a short-lived proposition at most.

A change of government federally, at an election sooner rather than later, is likely. This will be a good thing for politics across the board, because the Liberal Party needs time for reflection and regeneration.

Does it want to be a party of Trumpists? A party of Menzian Liberals? A socially conservative Howard-style government, pragmatically buying off swinging voters with middle-class welfare handouts election after election?

The Liberals need to work out who they are, what they are and who they can unite behind before their electoral fortunes can be restored. Good policy and good government in Australia should not have to wait while they sort themselves out.

Dr Chris Wallace is a Research Fellow (ARC DECRA) at the School of History, Australian National University. This article first appeared on The Conversation.