Right after Pearl Harbor there was incredible political pressure to do something about Japan. Natural enough. But Roosevelt wanted to deal with Germany first. He saw Germany was more dangerous. She was bigger than Japan, bigger population, far more heavily industrialized, had her own supplies of coal and iron, had plenty of top flight scientists, and occupied a very strategic location, right in the center of Europe. Europe was the center of the civilized world in those days, where as Japan was way off in the Far East. The US Joint Chiefs of Staff and most of the American establishment agreed with Roosevelt and supported his views on the matter. The British were all in favor. And, Hitler declared war on the United States. This was purely off the cuff on Hitler’s part, he had no alliance with Japan, no treaties offering support, and he didn’t own the Japanese anything. Five million German soldiers were locked in deadly combat with the Russians, the British were bombing the snot out of his homeland, last thing Hitler needed was another enemy. What Hitler did manage was to convince everyone in America that Germany and Japan were in league with each other (the Axis) and so nailing the Germans was as good as nailing the Japanese.
Had we followed our first impulse and thrown everything into smashing Japan we might have given the Germans time to develop nuclear weapons. We certainly would have given them time to get their deadly Type 21 submarines into action. We would have given Hitler time to beat down the Russians. Time for Rommel to stiffen the defenses on the Atlantic Wall. As it was, the Atlantic Wall was almost strong enough to defeat D-Day. Another year or two of laying more minefields, building more pill boxes, and it might have been strong enough to hold.
