By Adam Curtis
The idea of "humanitarian intervention" which is behind the decision to attack in Libya is one of the central beliefs of our age.
It divides people. Some see it as a noble, disinterested use of Western power. Others see it as a smokescreen for a latter-day liberal imperialism.
I want to tell the story of how this idea originated and how it has grown up to possess the minds of a generation of liberal men and women in Europe and America.
It is the story of a generation who became disenchanted with traditional power politics. They thought they could leap over the old corrupt structures of power and connect directly with the innocent victims of war around the world.
It was a grand utopian project that began in the mid-60s in Africa and flourished and spread across the world. But in the 1990s it became corrupted by the very thing it was supposed to have transcended - western power politics.
And the idea seemed to have died in horror in a bombing of a hotel in Baghdad in 2003.
What we now see is the return of that dream in a ghostly, half-hearted form - where the confidence and hopes have been replaced by a nervous anxiety.