Seven years ago she was the red rag and he was the bull. Helen Clark was the head girl and John Key hadn't been Teflon coated.

He couldn't have contemplated back then that his political body armour would have been even more impervious than hers, and she wouldn't have thought in her wildest dreams that she could have been in the running for the world's top political diplomat's job, heading the United Nations.

Even though she was running for her fourth term in office and the odds were stacked against her, she was astounded that the whipper snapper Key, after a political apprenticeship of just six years, could have knocked her off the perch she was so comfortable occupying.

In a couple of years Teflon John will be in the same position but the opinion polls would tend to suggest the odds for him are better than than were for Clark. But 24 months is a lifetime in politics and in this business nothing's certain.

Recovering in England from her defeat and her decision to quit politics, Clark came across an ad in the situations vacant column of the Financial Times and before too long she was United Nations bound.

So for Key all was forgiven as she settled into the Big Apple. She was happy to receive the new Prime Minister's texts and the pair are now more than comfortable in each other's company. He always drops in to see her for a cuppa in her Trump Tower office when he's in town, even bringing her tidings from home, like the odd jar of Marmite.

On his current trip Stateside they of course caught up again and she threw the cat among the pigeons by throwing her weight behind the polarising Trans Pacific Partnership.

Auckland law professor Jane Kelsey's claws would have scratched her eyes out if she was in striking distance.

It shouldn't have come as any surprise though to the learned Kelsey, given that Clark was in the box seat in Beijing when we did the free trade deal with China and where would we be today without that today?

Clark argues that it's better to be part of what Kelsey obviously sees as the dirty dozen countries negotiating the deal, than being the odd one out and that's hard to argue with even if the law professor sees it otherwise on many fronts.

The negotiations should have been more transparent, she says. But how you can negotiate an agreement by showing your hand to the other side is difficult to follow.

So Clark's now on board and in return her buddy Key says he'll do all he can to assist her if she decides to run for the top UN job.

If there's the opportunity, she will, but in reality Key's support will carry about as much clout as New Zealand does at the TPP negotiating table!