His gratuitous and rather coarse insult concerning David Beckham was hardly serious enough to cause a diplomatic incident but it did receive worldwide coverage and made front-page headlines in some British tabloids - and it is, sadly, the case that the person who came out of the episode with damage to his reputation was not David Beckham but the New Zealand Prime Minister.

This minor misjudgment may not matter much in itself, but it may be symptomatic of an increasingly casual and flippant attitude taken by the Prime Minister to the responsibilities of his job. On the same day as the Beckham comment, John Key - presumably in an attempt to show that he was "one of the boys" - ventured an ill-judged "joke" (this time on New Zealand radio) that managed to use the word "gay" as an insult.

The increasingly numerous "brain fades" that John Key has suffered in recent months, and the number of times that he has shuffled off responsibility on to other agencies when his government has been found at fault also suggest a political leader whose mind is not entirely on the job.