New Zealand’s former PM, reforming finance minister Bill English, was in Sydney last week saying things a centre-right politician would not dare utter here: an emissions trading scheme was the best thing that New Zealand had ever done on climate policy.

English is hardly a climate warrior. A wry, dry, and no-nonsense character, he’s a farmer from a town called Dipton, about an hour’s drive from the bottom of New Zealand, in a country where agriculture produces 48 per cent of the country’s emissions and has been the biggest contributor to emissions growth. To wit: former Prime Minister Helen Clark’s first abortive attempt to tax CO2 in the mid-2000s was derided as a '‘fart tax'’.