If you were the chief executive of an oil company hoping to defend your business against environmental campaigners, there are several ways you might go about it. The most direct approach, as adopted by ExxonMobil, would be to fund groups that claim climate change isn't happening and urge the White House to remove the head of the Intergovernmental Panel on Climate Change.
But you wouldn't do this if you had any sense: Exxon's tactics, while successful in the short term, have backfired spectacularly, confirming many people's impressions that the oil industry is a threat to life on Earth. If you were smart, you would follow BP and Shell's tactics. Rather than denying that climate change is happening, they have repositioned themselves as friends of the environment. Their new advertisements... seek to persuade us that they have left the bad old days behind...
Smoke and Mirrors: George Monbiot, New Scientist, 30 December 2006