Before the outbreak of war, Germany, Italy and Japan did virtually nothing to coordinate their policies or strategies. Italy remained neutral until the last stages of German conquests of France, and then pursued its own interests in the Mediterranean. Germany waged a war on two fronts and many a times, treated Italy as a 'client', ignoring or trivializing Italy's concerns (Bramsted, 1994). Japan waged its own war in Asia and ignoring Germany's request for assistance in the invasion of the U.S.S.R., most probably because they fear another defeat after suffering defeat at the hands of the Soviets at Nomohan in 1939. Italy's strings of defeats against inferior troops caused Italy to appear 'weak' by the Germans, while the Italians viewed the Germans as 'arrogant' for ignoring and trivializing many of their concerns, most notably the invasion of Romania by the Germans without informing Mussolini beforehand. Mussolini regarded Romania as part of its theatre of war.
All these factors contributed to the disintegration of their alliance, and Mussolini even contemplated withdrawing from the alliance in 1943. This eventually turned into reality when Mussolini was removed from power on July 25, 1943 and Italy switched to the Allies.
a) Differences in the Objectives of the Axis Powers
According to the Tripartite Pact (A summary of the Tripartite Pact was found on ibliblio website.) signed in September 27, 1940, under Article I:
"Japan recognizes and respects the leadership of Germany and Italy in establishment of a new order in Europe."
And under Article II: "Germany and Italy recognize and respect the leadership of Japan in the establishment of a new order in greater East Asia."
It can be seen that right from the start, there has been a difference in objectives of the Axis Powers. Germany and Italy pursue...