Foreign policy seldom wins elections, but it can certainly lose them. It can also ruin the reputation of an otherwise extremely successful politician.

That certainly looks like the fate of Tony Blair as the British prime minister limps out of office. In spite of remarkable achievements – not least in making his own Labour party the natural party of government in the UK after 18 years in opposition, in forging peace in Northern Ireland, stopping ethnic cleansing by Serb militias in Kosovo, and putting both global warming and African poverty high on the international agenda – he is quitting office with his reputation in tatters because of his fateful decision to join the US in a disastrous military intervention in Iraq.