During his time as Australia’s prime minister, John Howard first coined the phrase “scraping the barnacles” off the ship of state.

He used this reassuring term so that voters would look favourably upon him essentially throwing a pile of unpopular policies overboard.

It was meant to inoculate the PM against claims that he was breaking promises or backflipping on policies. And it worked most of the time.

One particularly memorable example of this tactic got quite an airing over the past week.

After suffering a 10 per cent swing in a by-election against his government in 2001, Mr Howard scrapped fuel indexation to neutralise voter anger over petrol prices.

He went on to win the federal election eight months later, and it is widely accepted that the fuel excise decision contributed to that success.

The Tampa affair and the September 11 attacks also helped.

Almost anyone with a political opinion and a public platform has encouraged Mr Turnbull this week to follow Mr Howard’s example in light of the similar drubbing in Longman.

But it seems an inordinate amount of faith is being placed in the assumption that everything will be rosy for the government if only Mr Turnbull scrapped the proposed tax cuts for big business.

This is more wishful thinking than a sound political assessment based on facts.

Bill Shorten and the Labor opposition have successfully framed the upcoming federal election as a contest of priorities, and tapped into voter anger about the Coalition having the ‘wrong’ ones.

Scrapping tax cuts for big business will be seen as a hollow gesture if there are still tax cuts for millionaires and ‘funding cuts’ for schools and hospitals.

This is the real barnacle build-up that’s slowing the Turnbull ship of state, and unless the government can convincingly demonstrate that it has the interests of all voters at heart, it will continue to risk foundering at the next federal election.

Shorten has his own barnacles

That’s not to say Mr Shorten doesn’t have his own barnacles.

The Opposition Leader has been uncharacteristically slow in dealing with the unedifying spectacle that has been the media exposé over the alleged behaviour of Labor backbencher Emma Husar.

Ms Husar has been accused of two serious breaches: bullying staff and misusing taxpayer funds.

In both cases, the allegations should have been directed to the relevant independent authorities for investigation, not left to an in-house review run by an ‘independent’ Labor lawyer.

The Labor Party will now be seen to be complicit in the outcome.

If Ms Husar is found to be innocent, Labor will be accused of a cover-up: if she’s forced to resign, the party will have exposed itself to accusations of a stitch-up.

The leaking to the media of the allegations against Ms Husar may even be perceived as a pre-emptive detonation of a ticking time bomb – an act of barnacle-scraping in itself.

In addition to Mr Turnbull and Mr Shorten, there’s one other politician who has probably had barnacles on his mind.

Tony Abbott made a couple of ‘helpful’ contributions on tabloid radio this week after the Coalition’s poor showing in the Longman by-election, claiming not to want to change leaders but to change the Liberal Party’s policies so that it can win the next election.

According to Mr Abbott, this change should involve abandoning Australia’s commitments under the Paris climate change agreement, slashing immigration to give infrastructure and integration a chance to ‘catch up’, increasing funds for Catholic schools and building new coal-fired power stations.

But the former prime minister’s chief tactician is much less coy about the particular barnacle she thinks should immediately be chipped from the Coalition ship of state.

Describing Mr Turnbull’s tenure in the prime ministership as “one man’s vanity project”, Mr Abbott’s former chief of staff Peta Credlin issued her latest ultimatum to the PM this week.

“If Malcolm Turnbull had any dignity and he actually cared about the party … he should actually resign,” said Ms Credlin.

“It shouldn’t be for the Liberal Party to knife another leader … I think he should have enough self-awareness to say that he’s not the man for the job.”