Despite the plethora of personal footprint calculators out there, I have always had the nagging feeling that personal choices make almost no difference on the environment – that the shift of responsibility for environmental woes to individuals is a corporate strategy meant to reduce pressure on producers and legislators to regulate radical improvements to industrial practices. A recent MIT study headed by Timothy Gutowski showed that, in fact, even a homeless person in the United States has a carbon footprint twice the world average. This is due to enterprise- and government-level decisions and practices, such as the military, road construction and the way services such as electricity and water are distributed. The study took special care to account for the “rebound effect,” which looks at how money saved on gas – by driving an efficient car, for example – is then spent on another product or service with a potentially greater footprint. He proposes a carbon tax on consumers as the solution – once again neglecting the most powerful decision-makers: the producers and legislators who are themselves empowered to make decisions on a national scale that will reduce the footprint of even the most ascetic of Americans.