OPINION: It's already been called #ponytailgate on Twitter but it won't bring John Key down - at least not directly.
John Key Photo: RNZ / Alexander Robertson
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What it will do is accelerate a process where the fuel of public popularity that drives him is withdrawn, prompting him to reassess whether his heart is in the job, as he did over the summer of 2012/13.
The Prime Minister's persistent pulling of a waitress' ponytail makes him look creepy and weird, and Mr Key is an astute enough political player to know it.
Like Tony Abbott and his wink, some will see a sexual element - and it seems unlikely the Prime Minister would pull the hair of a male waiter.
They may be a minority. But, just as bad politically, the majority will probably see it more in the category of Kevin Rudd and his earwax - an odd personal habit, and it does seem Mr Key is a recidivist, with Campbell Live footage emerging of the prime minister doing the same to a much younger girl.
Prime ministers can be hated by huge proportions of the population and survive, but they cannot become laughing stocks. That's the unmanageable risk faced by Mr Key. Appearing to seek the silence of the young woman with an apology and a couple of bottles of wine is also potentially embarrassing.
Inevitably, the question will be asked how the Prime Minister would respond were the same facts applied to, say, Paul Goldsmith, the local National MP in the café's electorate. Would Mr Key stand down his new Commerce Minister?
Is a prime minister repeatedly harassing a young woman working in his local café in the presence of armed Diplomatic Protection Squad officers - with all the power imbalances that implies - better or worse than the circumstances that led to the fall of Aaron Gilmore?
How does it compare with the circumstances that led Mr Key to rid himself of Judith Collins - especially since the allegations against Ms Collins were disproved by Mr Key's Chisholm Report?
There is growing dissatisfaction among the business community and elements of the National Party caucus and cabinet about Mr Key's lack of policy ambition. His prime ministership is kept alive by his personal popularity and the emotional return he draws from it. If either fades, Mr Key will want to throw in the towel.
And, under those circumstances, many on the political right will be pleased to see him go.