Last year the UN Intergovernmental Panel on Climate Change warned that unless the world's mean temperature is stabilised - prevented from rising by more than 2C - we risk runaway climate change. That meant 80 per cent of known coal, oil and natural gas reserves must be kept in the ground as "stranded" assets, worth nothing. The fossil fuel industry has ignored this threat; those undeveloped assets are a huge part of its market wealth.
The Westpac protesters came from two groups, 350 Aotearoa and the Coal Action Network Aotearoa. As the energy industry drills, fracks and mines around the globe, the US parent of one of those organisations - 350.org - has emerged as its nemesis, wielding a potent weapon: divestment.
Protesters want investors to withdraw support from 200 fossil fuel companies, including huge players such as ExxonMobil and Chevron. It's a war in which Westpac suddenly found itself cast as a bad guy by the emerging divestment movement.
While divestment is an economic strategy, the campaign is pitched as a moral crusade aimed at universities, pension funds and other big investors. The Kiwi end of the campaign has held divestment forums, sent letters to institutions asking them to sell fossil fuel stocks, and staged flash mob events at Westpac branches.
"Protesters went to Westpac's Cuba St branch in Wellington and symbolically withdrew $1 from their accounts," says Ashlee Gross, 350 Aotearoa's national co-ordinator. "To remind them we are customers and have the power to remove our money."
A dollar is a piffling amount, but the symbolism is significant; fossil fuel divestment is already under way in New Zealand. The Anglican Church has divested. The Church sees divestment as a moral issue because climate change in our region would harm people who are least responsible for rising temperatures: Pacific Islanders faced with rising seas.
While state-owned funds, notably the NZ Superannuation Fund, with $440 million (2.3 per cent of its capital) invested in fossil fuels, according to a World Wildlife Fund report last year, and the Accident Compensation Corporation, with $626.8 million invested (3.4 per cent), have shown willingness to stop investing in the nuclear industry, they seem less likely to follow the Church's example when it comes to fossil fuels.
Westpac said it "provides banking services to Bathurst Resources, but has not been involved in financing Bathurst's Denniston Escarpment Mine Project".
Which is arguably disingenuous, as a loan was made in 2012 to Bathurst's Cascade Mine on the edge of the Denniston plateau, the beachhead for Bathurst, which is gearing up for larger-scale mining on the plateau.
"We're not trying to shut down the Cascade Mine," says Gross. "We made it clear to Westpac [at a November meeting] we understood the loan wasn't specifically for Denniston. But that doesn't mean it didn't enable the funding of Denniston ... there's no financial separation between Bathurst mines. It's not like they are different corporations or different subsidiaries. And Bathurst made it clear to their stakeholders, in putting that information out publicly, that the profit they were making from Cascade was going into Denniston."
However, Hamish Bohannan, Bathurst's chief executive, says Westpac's earlier support is "totally unrelated" to present developments, that the company is "almost debt free" and present work is funded from equity. While acknowledging the need to "step away from fossil fuels" because of climate change, he says the 350 campaign is "sleight of hand", as on the West Coast Bathurst mines high-quality metallurgical coking coal, used in steel production, and there is no alternative fuel. He points out that steel is used as a raw material in many renewable-energy industries, "and we wouldn't have the tools to get alternative power without coal in the first place. It is a journey".
The company says it will provide 400 direct jobs, 200 of them on the West Coast, and generate $1 billion for the New Zealand economy. This is a selling point for Bathurst and a stick with which to bash critics. "It's the most difficult part of campaigning to stop a coal mine," says Gross. "I'm intensely aware it would have a short-term, direct impact on people. I wish that wasn't so. But we know coalmining is