The Germans advance deep into Russia, they reach the gates of Moscow. And then the snow comes. The U Boat campaign is causing major disruption to shipping in the Atlantic. Tobruk is besieged. Japanese troops reveal their country's true expansionist plans by occupying Southern Vietnam and Cambodia ("French Indo-China") having already occupied the northern region (Laos). But the day that changed the war came at the end of the year, on December 7th. President Roosevelt called it "a day of infamy" - Japanese carrier-born aircraft attack the American Pacific Fleet at anchor in Pearl Harbor.