What the Japanese should have done was to ignore the United States completely. They had USA sanctions against them but their best course of action would have been to cement the Axis Pact and invade Russia.
Their troops in Manchuria would have driven northwards and cut the Trans Siberia Railway. This would have isolated the Russian Far East Army which was pivotal in halting the German advance in the west. In fact they were kept in the Far East until Pearl Harbour for this very reason. They could then put the Sino Japanese war on hold, if not by truce but by inactivity. Chiang Kai Shek would immediately, knowing that the Communists would be having supply problems from the Soviet Union, go at Mao’s throat and clear up his own problem.
The Wehrmacht, unhampered by the Far East Army would have continued their advance east of Moscow leaving Leningrad and Stalingrad withering on the vine.
The United States would have no reason to join in the war. In fact the Japanese actions against Russia would be admired by many Republicans. The problems for Roosevelt would come later.
The Japanese, now being fully paid up members of the Axis would now be at war with the UK. Using Germany’s right of conquest over France and Holland they would occupy Indo China and Sumatra. These would be used as a base to overrun Singapore and the Solomon Islands which would ring fence Australia and New Zealand making their troops unavailable to the UK.
The Germans, meanwhile would have advanced into Southern Asia and may have been in a position to advance down the eastern side of the Persian Gulf thereby putting them in a position to isolate India and Ceylon.
Luckily for us the Japanese went for Pearl Harbour.