It’s been a troubled week for Malcolm Turnbull, with portents of problems that may not be so easily fixed. Here are three:

The leaks have started

Labor has had access to private government documents designed to prevent Tony Abbott from being blamed for approving Stuart Robert’s very official-looking private trip to China with his friend Paul Marks (Marks being a big donor to the Liberals and Robert being a shareholder in companies associated with Marks.) When Bill Shorten can stand up in the parliament and quote the serial number of government correspondence on the issue, it’s an ominous sign.

Tony Abbott’s “no wrecking, no undermining and no sniping” promise has looked shaky from the start, with his very pointed interventions, and the provenance of the leaks cannot be proven.

But when one of Abbott’s favourite columnists writes “blame shifting on this issue is a risky strategy considering there are still spear throwers in the party room who won’t tolerate much more revisionism from Turnbull’s camp” it looks pretty much like a direct threat from Abbott’s “camp”.

Meanwhile, Scott Morrison had earlier dismissed the affair as “a massive beat-up” and made a point of walking into question time alongside Robert, his friend, flatmate and supporter, so loyal that he is understood to have switched his vote from Abbott to Turnbull in line with Morrison’s own defection.

Robert has now been sacked without reference to Abbott’s knowledge of the purpose of the trip. And the post-leadership coup bitterness does not seem to have deteriorated to the level of the deliberate and devastating leaks against Julia Gillard in the 2010 election campaign. But the signs are not good.

The loud man has landed

New Nationals leader and deputy prime minister Barnaby Joyce is certainly good at “selling a message”, it’s just not always the same message that Malcolm Turnbull’s Liberals want to sell.

On Friday he described the Coalition agreement as “a business partnership and not a marriage”.

“At certain times the business partners have different views on things but I’m not going to go searching for them,” he told the ABC.

Joyce, who is certainly better at long-term strategising and biting his tongue than when he entered parliament in 2005, is unlikely to make a public fuss about the Nationals’ “different views” in the lead-up to this year’s election, but the whole point of electing him is for him to do exactly that in the longer term. As country independents nip at their heels, Nationals believe their long-term survival requires them to “differentiate” more – have their disagreements with the Liberals more publicly so rural folk know they have been had.

The shake-up means there a now several potential Coalition disagreements in the offing.

Competition policy. The Nationals insisted the reworked Coalition agreement with Turnbull included a promise to reconsider competition laws protecting small business from big businesses abusing their market power. Turnbull has opposed the changes in Cabinet.

Environment policy. The Nationals have, for example, been angered by the federal environment department’s attempts to implement federal laws on land clearing and have spoken out against the government’s renewable energy policy.

Welfare policy. The Nationals go into bat for single-income families, whereas the Liberals like to encourage parents back to work. The same Coalition agreement included a pledge to pay an extra $1,000 to single-income families with a child under one who earn less than $100,000 a year, but that was part of a deal with the crossbench that hasn’t made it through the Senate.

Climate policy. Barnaby, like many of the Nationals he leads, is not sure about the whole theory of human-induced climate change. Turnbull is. Hard to see how that difference wouldn’t play out when it comes to climate policy.

The tax policy has fallen apart

It’s not usual for governments to release internal modelling to show why they’re not doing something they’ve just spent months suggesting they will do. Not necessarily a bad thing, in my view, attracted as I am to evidenced-based policymaking, but certainly unusual.

But ditching the “big bang” tax cuts does not tell us how they intend to pay for the “quietly modest” tax cuts they are now foreshadowing. But we can be pretty certain gradual long-term personal tax cuts are likely because the government is using the same modelling to present bracket creep as the problem the exercise is designed to solve. Whether voters think bracket creep is a bigger problem than the stuff Labor intends to pay for (schools and hospitals), probably with a similar set of tax changes, remains to be tested. Right now Labor has the great advantage of at least the beginnings of an actual policy, with more on negative gearing and capital gains tax released today.