The award itself is no surprise: the Nobel has long seemed destined to land eventually in Mr Krugman's lap. Yet eyebrows will be raised both by the timing and by the fact that Mr Krugman is the sole recipient of the award.
The timing is provocative, three weeks before the US presidential election, because Mr Krugman has been a trenchant and influential critic both of the Bush administration and of John McCain. Then there is the Nobel committee's decision not to split the prize – as is common – with economists whose work is related. Men such as Avinash Dixit made Mr Krugman's research possible. Yet while Paul Krugman's talents as a theorist are shared by a handful of his peers, his gifts as a communicator are not. It seems that the Nobel committee felt that Mr Krugman's role as a public intellectual was a stepping stone to the prize, not a stumbling block.
That is no bad thing. As the world is once again realising, economics matters. Mr Krugman has always been an exemplar of clear economic thinking and a champion of data over anecdote. He was a perceptive analyst of the Asian crisis and has been a sharp, witty defender of globalisation. His readers were warned in good time to beware of the dot-com craze and the housing bubble, learning about the economy through parables about a baby- sitting circle, a gold rush or a hot-dog manufacturer.