In the process, she delivered an even better distraction for him.
It was Ardern's John Key Superannuation moment – a pledge made for political reasons.
In 2008, Key had said he would resign if he made any changes to superannuation.
That was done to quell Labour's claims he had a secret agenda to raise the retirement age and even maybe means test super.
Labour had made it clear that Auckland was the only region allowed the tax in the short term, but it had left the door open to others to apply after 2020.
That was always going to be a headache for Labour as 2020 loomed and National wrought havoc by warning regional fuel taxes were coming for other regions.
National was more than happy to do that - drivers in the regions already feel they are subsidising Auckland's regional fuel tax, with good reason.
After her declaration, Ardern's office insisted it was not policy on the fly and Ardern had always made it clear behind the closed doors of Cabinet Committees that she would not allow any regions other than Auckland to have it.
If so, it seems bizarre she did not say so publicly at the time – and that the prospect of post-2020 fuel taxes had always been in play. In fact Transport Minister Phil Twyford had told councils to work with the Ministry of Transport on their bids if they were keen.
It certainly came as a surprise to coalition partner Shane Jones, the Regional Development Minister.
Jones was filling in for Transport Minister Phil Twyford in Parliament.
Asked when he had first known of the decision not to allow any further regions to get the fuel taxes, Jones said it was when the Prime Minister had stood up moments before him and announced it.
Ardern's announcement will also come as a surprise to those 14 councils who had been told to work with the Ministry of Transport on their bids for post-2020.
Councils – including Hamilton - have long called for more ways to raise revenue to help stem rates increases. The tax was dangled tantalisingly before them. They have now been told it is forbidden fruit.
The first response was to wonder where the money for roading projects would come from now.
There are no prizes for guessing who's putea [purse] they'll be calling on first – the billion dollar stash of Jones.
Whether it's a backflip or not will not matter to the drivers of the regions.
Ardern got rid of a political hot potato and saved herself the problem of performing the exact same back-flip in two years' time. The timing of it suited Bridges too.
Bridges will take victories where he can and here it came in finally getting people talking about petrol again rather than his leadership.