Now some of the savviest investors in the world are adopting a new catchphrase, "Green is good", because in the long run investing in technologies that reduce carbon emissions is cheaper and more profitable.
The political focus this week was on the United Nations Climate Summit in New York, where Leonardo DiCaprio called for action and police arrested a protester dressed in a polar bear suit.
But the economic and investing focus was on the Global Commission on the Economy and Climate's release of a 10-point plan recommending ways to accelerate economic growth and address climate change at the same time, often by cutting subsidies and reducing public spending.
"The New Climate Economy report has shown it is possible to have better growth and a better climate. It is possible to create jobs, reduce poverty and reduce the carbon emissions that threaten our future," said commission chairman and former Mexican President Felipe Calderon.
The commission is not short of high-powered global corporate types. Alongside UN Development Programme chief Helen Clark, the Commission has the chief executives of Unilever, Bloomberg and Swiss Re and the executive director of the International Energy Agency.
It pointed out that taxpayers globally spend US$600 billion a year on subsidies for fossil fuels. The health costs alone of pollution from coal surpassed the equivalent of 6 to 11 per cent of GDP a year in countries that include China, Russia and India.
The International Panel on Climate Change has already estimated that a 2C increase in temperatures by 2050 would reduce Global GDP growth by up to 2 per cent a year.
Big global businesses and the biggest governments are realising action to mitigate climate change would reduce the immediate costs by lowering subsidies and bring down long-term costs by avoiding the inevitably slowing effects of climate change on global growth.
That was most poignantly illustrated this week when the Rockefeller Brothers fund, created from the profits of John D Rockefeller's Standard Oil fortune, said it was divesting out of fossil fuels.
They hope to focus attention on this issue in a similar way to those funds that pulled out of companies linked to apartheid in the 1980s and 1990s, helping to accelerate its demise.
Even our own New Zealand Superannuation Fund said this week it was joining a group of funds commissioning a study by Mercer of the investment risks and returns under various climate-change scenarios.
"This project will help us calibrate our investment strategies accordingly," said NZ Super Fund chief executive Adrian Orr.
Fund managers, bankers and insurers have now moved from warning of the risks to the economy from actions to address climate change such as carbon taxes, to warning of the risks to their balance sheets and profits from not addressing climate change.
Rightly, they're beginning to look at the longer term and global effects of their investment decisions and the decisions governments make about taxes, subsidies and spending.