Like many things in history it's a matter of perspective and opinion. What's yours?Could it be that Hitler declared war on the U.S. because the U.S. had gone to war against Japan over Pearl Harbour and Japan was Germany's ally?Could it be that Hitler was a slave to his ego?Could it be One of the big reasons was that the Japanese ambassador to Germany had hinted that if Germany declared war on the USA, the Japanese might declare war on the Russians and help him out of that sticky situation?Hitler also expected that sooner or later the US was going to go to war with Germany and the sooner that happened, the sooner he could unleash his U-boats against the Lend-Lease convoys sustaining British resistance to him.What's your opinion?