It was supposed to instruct, to keep us alert to the danger of fascistic recrudescence. Once viewed, never forgotten. Jeremy Isaacs's The World At War was the grandfather of the genre - and also the model that has never been bettered. Laurence Rees's The Nazis - A Warning From History took the warhorse in hand for another successful canter. But there's an iron law in British television that decrees that a failing genre has to be pursued way beyond the point of diminishing return.
Television looks immediate but is slow on the uptake.
The business is expensive and money is allocated through slow and painful channels. Ideas that seem prescient often turn to celluloid ash by the time the programmes arrive on screen. Now British television's id e fixe lurches into its decadence. The Swastika took a profound theme - German science in the service of racism. Eva Braun's over-familiar films of life at the wolf's lair flickered before our lazy eyes.