branwen jefferies, bbc news, south gloucestershire. on bbc two. thousands of flames have been lit for a second night at the tower of london to mark the centenary of the end of the first world war. the installation called beyond the deepening shadow will run each night until armistice day, november 11th. our special correspondent allan little reports on how britain's understanding of the war and its consequences has been transformed over the past century. no war in history had demanded so much, mobilised so many or killed in such numbers. and when it was over, the men who fought it began asking questions that have never gone away. what was it for? and was it worth it? we remember them now, with public reverence, but the way that we think about the war they fought has changed dramatically in the 100 years since it ended. this is dryburgh abbey in the scottish borders, where britain's military commander, earl douglas haig is buried. when he died ten years after the war ended, he was a venerated public figure. the architect of victory and