Heather du Plessis-Allan: Balance is vital for Peters and NZ First

It's a deal. Jacinda Ardern and Winston Peters shake hands on the Coalition Government in 2017. Photo / Mark Mitchell

For a good few months theories have done the rounds on exactly how Winston Peters and NZ First plan to disrupt the Coalition Government to their advantage in the run-up to the election.

The theory makes sense. Disruption gets them headlines, differentiates them from the bigger party and allows them to cast themselves as the commonsense handbrake on Labour's ideological excess. And everything has pointed to that theory actually being the plan. Peters and his mob seem to be going out of their way to cause headaches for Jacinda Ardern and Labour.

But if Peters thought he was on to something clever, he might have met his political match. Ardern is outmanoeuvring him with a simple strategy: she is smothering him with kindness. And by doing that, she's leaving him very little room to move.

In the last month, Peters has thrown a couple of curveballs big enough to irritate any PM. His rhetoric over China was undiplomatic enough to earn a rebuke from the Chinese ambassador and require the PM to mop up after him, using her regular 1pm press conference to remind the Chinese New Zealand hasn't changed our one-China policy. Peters' choice of language was so reckless and his determination to pick a fight with China so transparent it led to open speculation that he was trying to get fired from the Coalition.

All the while, his stalling of Justice Minister Andrew Little's deft commercial rent solution was inexplicable. Little's solution was pragmatic and nicely avoided the trap of the Government paying everyone's bills during this crisis. The concessions Peters is proud of extracting over the last two months - especially cutting out big business tenants from the solution - were not worth crowing about. He can hardly expect to win applause from small businesses after delaying help they needed two months ago. For Labour, that delay caused mounting risk that they would be the party accused by small business of not helping out sufficiently.

And yet Ardern remained relaxed. She never showed irritation at her rogue deputy. She never told him off. She only made excuses for him. She's past the point of looking weak by doing that. In fact her political capital is so high at the moment that she can afford to spend some on coalition management.

And the result is that Peters' disruptive behaviour increasingly looks less like a commonsense handbrake on an ideologically obsessed and naive government, and more like reckless politicking ahead of an election. The PM increasingly looks like the mature one of the pair and Peters like the rogue she must apologise for.

By constantly moving towards Peters and covering for his behaviour, the only direction he has left to move is further away from Labour and towards more disruption. But, by doing that, he risks only looking more reckless and political. Peters should think twice about pursuing that strategy given he already has a reputation as being a spoiler in previous governments.

If Peters chose Labour over National three years ago because it looked the easier touch - a party more desperate after nine years in opposition with an inexperienced, young leader - he might've called this one wrong. Because Ardern has surprised most with her coalition management. For all her errors, she has undoubtedly done an excellent job of keeping this coalition together and handing out enough wins to keep all happy.

That's not to say it'll stay happy campers through to September 19. Shane Jones this week made it clear that NZ First will "well and truly distinguish" themselves over the next 12 weeks. But after issuing that warning, he then went on to admit "there is a balance". Jones and Peters are smart and experienced enough to know there is a line to be walked: they must disrupt for their own survival - but not too much. The trouble is the PM knows this too and is making that line very hard to walk.