The spectacle of US President George W. Bush exhorting other countries to follow his lead in tackling climate change came as a puzzle last week to many. Since a 2001 speech in which he questioned the science of global warming, he had barely mentioned the subject until his State of the Union address this January, when a single mention crept in. Now the White House is seeking to be portrayed as leading the pack.

“What I’m telling you is that we’ve got a strategy, we’ve got a comprehensive approach,” Mr Bush told senior government officials from the world’s 16 biggest greenhouse gas emitters, including the US, who had gathered in Washington last week at his behest, “and we look forward to working with you as part of this global effort to do our duty.”