The scale of risk from climate change is altogether of a different and greater magnitude, as are the consequences of mismanaging or ignoring it. The US, in particular, has a window of opportunity to act on the financial crisis and, at the same time, lay the foundations for a new wave of growth based on the technologies for a low-carbon economy.

President Barack Obama, in his speech to Congress and budget last week, explained that we need to address both of these challenges, and outlined a broad approach. US leadership could generate a power- ful response from across the world, making possible an agreement at the United Nations climate change conference in Copenhagen in December on a scale necessary to manage the risks involved.

We will eventually emerge from the financial crisis, although mistakes in management can affect its depth and duration. However, mistakes in managing the risks of the climate crisis may be irreversible. As noted in Making Globalization Work*, if we had a thousand planets we might continue with the reckless experiment on which we are embarked, and if the likely disaster occurred we could move on to another. Unfortunately we do not have that luxury: we have only one planet.