Afghanistan: one of the most isolated and barren landscapes on earth is a strange place for an empire or a superpower to invade. But for three of the greatest powers the world has seen, it became an unlikely target and an enduring obsession. / The 19th century British invasions into Afghanistan, immortalised by Rudyard Kipling as ‘The Great Game', ended in a huge loss of life, a British retreat and created a template for the perils of incursion in this mountainous country. / In this two-part series ﻿Rory Stewart MP - author, journalist and former deputy governor during the coalition's occupation of Iraq - travels to Afghanistan to uncover the fears, the paranoia and perceived threats that led three very different superpowers - Britain, Russia and the United States - into Afghanistan from the 19th century to the present day. (Source: BBC)