If Australian voters didn’t know the name of the Prime Minister’s most senior adviser before, they certainly do now after chief of staff Peta Credlin joined her boss at the centre of the latest political storm over the decision to award an Australian knighthood to the Duke of Edinburgh.

One News Corp columnist argued that, despite her having no part in the knighthood decision, Ms Credlin should be held responsible for not protecting Tony Abbott from his lapse in political judgement.

The columnist urged the PM to sack his chief of staff as a sign of penance.

Then News Corp owner Rupert Murdoch weighed in, telling the PM via Twitter that Ms Credlin must go.

Abbott again. Tough to write, but if he won’t replace top aide Peta Credlin she must do her patriotic duty and resign. More

— Rupert Murdoch (@rupertmurdoch) January 28, 2015

There is more to Mr Murdoch’s intervention than meets the eye: Foreign Minister – and potential alternative PM – Julie Bishop dined with the News Corp maestro just last week in New York.

Well-placed leaks to the media have made no secret of the poisonous working relationship between Ms Bishop and Ms Credlin, which culminated late last year in the Minister stating she would no longer take orders from the PM’s chief of staff. So it is way beyond coincidence for Mr Murdoch to urge the removal of Ms Credlin to “recover team work and achieve so much possible for Australia” so soon after meeting with Ms Bishop.

As Mr Abbott’s gatekeeper and lightning rod for disgruntled MPs, Ms Credlin isn’t new to complaints being made about her. But this time she’s been drawn into what could be a fatal battle – between those Liberals who want the PM to succeed, and those who want him to fail.

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Some Coalition MPs have been complaining about Ms Credlin since the government’s electoral prospects started to go downhill last year. Ms Credlin’s command and control approach to running the Prime Minister’s office and her protection of Mr Abbott from the day-to-day complaints of backbenchers and ministers have made her an easy target for anxious MPs.

As a result, Ms Credlin has been blamed for much of the government’s woes.

Calls for her removal reached a crescendo late last year, apparently on the basis that if more people could talk to the PM, the government’s prospects would magically improve. But then the complaints became muted when a few of the agitators were promoted in the December reshuffle of the ministry.

Little mention was made of Ms Credlin as the new year dawned, despite the PM continuing to show poor judgement, such as the decision to cut the Medicare rebate for short consultations and putting a media-free trip to Iraq ahead of visiting bushfire zones around Australia.

Disillusioned and disheartened Liberal MPs looked instead to the real cause of the government’s woes – the Prime Minister himself – and speculation about Mr Abbott’s tenure began to gain momentum.

When the announcement to knight Prince Philip was first made on Monday, the media’s focus was on Mr Abbott, his lack of political judgement, and whether this out-of-touch “captain’s call” signalled the beginning of the end for the Prime Minister.

Yet the two very deliberate interventions from News Corp on Tuesday brought Ms Credlin back into the picture.

Superficially, both actions appear to be similarly motivated, reflecting the PM’s supporters who think Ms Credlin is the problem and that the government will flourish again if she is excised.

While Ms Bishop may have argued to Mr Murdoch that the PM’s performance would improve with a new chief of staff, it’s likely she has come to the same conclusion that is beginning to dawn on many others – and that is that Ms Credlin has been the PM’s safety net. Without “the boss” as he calls her, and “Ms No” as she is known to others, Mr Abbott would have made even more poor political decisions.

Mr Murdoch may think he was helping the PM, but his intervention has played nicely into Ms Bishop’s hands. If Mr Abbott removes Ms Credlin he will not only be pilloried for doing the media mogul’s bidding, but also lose the only person capable of stopping him from making more politically questionable decisions.

Any further deterioration of Abbott’s credibility would strengthen the resolve of MPs currently vacillating about the need to remove him, without Ms Bishop being seen as the coup leader.

And if the PM remains loyal and keeps his most trusted adviser, this may also motivate those MPs muttering that the only way to remove the chief of staff is to remove her boss too.

Political staffers are not meant to make the news, and when they do it’s a sure sign that bad political judgements are being made.

However the drawing of Peta Credlin into the debate over the PM’s decision to award a knighthood to Prince Philip is not about her political judgement, or even her ability to police the PM’s. This is about a battle for the future of the Coalition government by Abbott supporters and their Liberal Party foes.

Ms Credlin has just become the most likely to fall in their political crossfire.

Paula Matthewson was media adviser to John Howard in the early 1990s and then worked for almost 25 years in communication, political and industry advocacy roles. She is now a freelance writer and communications strategist. Paula has been tweeting and blogging about politics, the media and social media since 2009 under the pen name @Drag0nista.