Award winning historian, Laurence Rees, answers the key question - How best can we compare Hitler and Stalin. Laurence's latest book 'Hitler and Stalin: The Tyrants and the Second World War' has recently been published in the UK and in America. It was described as 'always compelling' by the Times, 'an impressive parallel study' by the Telegraph, and the Times Literary Supplement concluded that 'as this book brilliantly shows, Adolf Hitler and Joseph Stalin were blood brothers.'