Chapter 12.The Second World War 12.1 Neutrality Acts (1935-1937) 12.2 The Blitzkrieg (1939) 12.3 Pearl Harbor Air Raid (1941) 12.4 The Manhattan Project (1942) 12.5D-Day(1944) 12.6 Hiroshima Nagasaki (1945) 12.7 Legacy of W IlChapter 12. The Second Chapter 12. The Second World War 12.1 Neutrality Acts (1935–1937) 12.2 The Blitzkrieg (1939) 12.3 Pearl Harbor Air Raid (1941) 12.4 The Manhattan Project (1942) 12.5 D–Day (1944) 12.6 Hiroshima & Nagasaki (1945) 12.7 Legacy of WW II