Thirteen months after the Molotov-Ribbentrop Pact had alienated Tokyo from Berlin, German-Japanese relations were reestablished on the basis of a military alliance. On 27 September 1940, Tokyo, Berlin, and Rome signed a Tripartite Pact. At this point in time, when the central conflict in the European war was the air battle between the Royal Air Force and the Luftwaffe, Japan hoped that this alliance might be directed at Great Britain. Tokyo urged upon the Germans an entirely different revolution in world political economy than the one German planners envisioned. Rather than colonizing the Soviet Union, thought the Japanese, Nazi Germany should join with Japan and defeat the British Empire.
The Japanese, building their empire outward from islands, understood the sea as the method of expansion. It was in the interest of Japan to persuade the Germans that the British were the main common enemy, since such agreement would aid the Japanese to conquer British (and Dutch) colonies in the Pacific. Yet the Japanese did have a vision on offer to the Germans, one that was broader than their own immediate need for the mineral resources from British and Dutch possessions. There was a grand strategy. Rather than engage the Soviet Union, the Germans should move south, drive the British from the Near East, and meet the Japanese somewhere in South Asia, perhaps India. If the Germans and the Japanese controlled the Suez Canal and the Indian Ocean, went Tokyo’s case, British naval power would cease to be a factor. Germany and Japan would then become the two world powers.
Hitler showed no interest in this alternative. The Germans told the Soviets about the Tripartite Pact, but Hitler never had any intention of allowing the Soviets to join. Japan would have liked to see a German-Japanese-Soviet coalition against Great Britain, but this was never a possibility. Hitler had already made up his mind to invade the Soviet Union. Though Japan and Italy were now Germany’s allies, Hitler did not include them in his major martial ambition. He assumed that the Germans could and should defeat the Soviets themselves. The German alliance with Japan would remain limited by underlying disagreements about goals and enemies. The Japanese needed to defeat the British, and eventually the Americans, to become a dominant naval empire in the Pacific. The Germans needed to destroy the Soviet Union to become a massive land empire in Europe, and thus to rival the British and the Americans at some later stage.
Japan had been seeking a neutrality pact with the Soviet Union since summer 1940; one was signed in April 1941. Chiune Sugihara, the Soviet specialist among Japanese spies, spent that spring in Königsberg, the German city in East Prussia on the Baltic Sea, trying to guess the date of the German invasion of the Soviet Union. Accompanied by Polish assistants, he made journeys through eastern Germany, including the lands that Germany had seized from Poland. His estimation, based upon observations of German troop movements, was mid-June 1941. His reports to Tokyo were just one of thousands of indications, sent by intelligence staffs in Europe and around the world, that the Germans would break the Molotov-Ribbentrop Pact and invade their ally in late spring or early summer.