Malcolm Turnbull knows what a leadership spill is like, from both sides of the debate

MALCOLM Turnbull knows better than most that once the rumblings start about a leadership spill, it generally means just one thing: A leadership spill.

It may not come next week, it may not come next month, but it will come – and almost certainly before the next federal election.

The prime minister has experienced those rumblings from both sides of the leadership fence, so none of the machinations set to play out in the Liberal party room over the next week or so will surprise him.

Mr Turnbull heard the rumblings himself when he was leader of the Liberal Party in opposition in 2009 and it wasn’t long before he’d lost the job to Tony Abbott.

Then, after Mr Abbott had led the party to an election win in 2013, it was Mr Turnbull and his supporters who began agitating for change, denying any move against the PM until the move was made.

This time round it’s Peter Dutton whose name has been linked to a leadership spill, though Mr Abbott is said to be one of his key backers behind the scenes.

And as was the case in 2009, energy policy is set to be Mr Turnbull’s Achilles heel.

As a centrist Liberal leader, Mr Turnbull has always been vulnerable to attacks from the conservative base and debate over the best energy policy for the country – one which gets the balance right between delivering lower bills for households while also protecting the environment – is an obvious point of contention.

The problem for Mr Turnbull on that front – and the entire Liberal Party – is that the two can never work together so the issue is never likely to be adequately resolved.

That means continued instability for the Liberal leader, whoever it might be, and continue free kicks for the Labor Party who must be barely able to believe their luck all over again.

Bill Shorten, after a difficult few months, again appears to be a genuine contender for The Lodge without doing anything of note to reverse the popularity polls.

As is often the case for an opposition leader, doing nothing and waiting for the government to implode looks to be Mr Shorten’s best tactic between now and the new election.

But who will he will face at the polls?

That question may take some answering yet, and there could be some real pain for the Liberal Party and its supporters before a final decision is made.