WW2 the big questions: the early years of the conflict

Why did Hitler make the fateful decision to invade Poland in 1939? How did Churchill turn defeat at Dunkirk into a victory on the home front? And why did Japan’s imperial designs lead to war in east Asia? In the second episode of our five-part series tackling the big questions of the Second World War, historian Laurence Rees joins Rachel Dinning to guide you through the early years of the conflict – from Pearl Harbor to the fall of Tobruk.