When Elton John released his mournful ballad "Sorry Seems To Be The Hardest Word" in 1976, I don't think he was thinking about politics.

But "sorry" really does seem to be the hardest word when it comes to politicians.

The Prime Minister has finally uttered the "s" word over email smears sent by his former aide Damian McBride about Tory Party figures.

But why are politicians so reluctant to say it?

No matter which walk of life it may be, people always give more credit to those who hold their hands up and say sorry when something has clearly gone wrong.

It is only a little word of five letters but it has extraordinary power to defuse situations.

It is nearly a week since Mr McBride quit. I wouldn't mind betting that Gordon Brown is sorry he didn't say sorry sooner.