About now the fate of the French fleet comes into bitterly sharp focus.
If it had stayed in (fighting) allied hands, then the North African campaign would have been a great deal easier - Italy’s fleet would have been bottled up with more capacity to spare. The Med would have become an English lake, though German air power would still have been a formidable problem. The Afrika Korps might never have established any kind of foothold in North Africa.
Also Singapore would have been far more secure. All those extra battleships, and suddenly the early war in the pacific might have had a different character. Japan might have ‘gone north’ instead, Russia would have fallen and the whole world be different today.
All depending on the fate of the French fleet.
As it was, the fleet had to be sunk. If the Germans had taken it intact, then the war would have been over in weeks.
As long as the U.S continued its embargo of Japanese purchases of metals and particularly petroleum, there was no way the Japanese would go north. The Navy wouldn’t allow it.
I really think the bloody nose the Japanese received at Nomonhan complements of Zhukov last year pretty much dashed any ideas of making a northern move against the Soviets. The Japanese will sign and cling to a non-aggression pact with the Soviets even before making a move for the Dutch East Indies. Couple that with the Navy-Army power struggle shifting to the Navy, the move for resources southward almost became inevitable.
Another move that could have happened would have been through India though. If the Nazi’s and the Japanese were committed to creating a physical border they both could have made moves through the southern belt of Asia. Japan into India and Germany, via North Africa, through the Middle East. As it stood though, the two powers were never very interested in the others sphere of interest and no concerted effort was made to join up. Japan did eventually invade India, but not until 1944 when it was pretty much over anyway, and the attack was a disaster. Germany never put the resources into North Africa to allow a push all the way into the Middle East, and the successful coup in Iraq moving it to Germany’s sphere of influence was quickly crushed by the British.