The more vulnerable a country is to Western pressure, the more likely its leaders are to step down when a revolution comes.

If President Hosni Mubarak had not been America's ally, he might still be in his impressive palace in Heliopolis now.

Colonel Gaddafi has so far managed to hang on because he is too way out, too friendless internationally for anyone to be able to stop him using his tanks and air force to bombard his own people.

So the West's care for human life and its free press are great at bringing down the less extreme dictators and not so good at bringing down the really nasty ones.

It is something to muse on.

How foreign media affect revolutions - http://news.bbc.co.uk/1/hi/programmes/from_our_own_correspondent/9421899.stm