What if, either Singapore (and by default Malaya) was successfully defended, or it was basically abandoned rather than men and materiel being wasted to a lost cause. As per usual this idea is growing exponentially and resulting and lots of reading and more ideas, through in some Hearts of Iron IV trying various things and it gets even weirder.
Just some interesting things I've come across.
Many, if not most, Regular Australian (senior) Officers believed that the Singapore strategy was deeply flawed and impossible to carry off as it relied citizen soldiers, conscripts and colonial troops, being able to defend against seasoned, highly motivated professional Japanese troops. This was assuming the planned (significantly less than the requested) numbers of men and scales of equipment were delivered.
Senior British officers requested approximately 50% more forces than they were promised, they received about half of the promised amount.
Gordon Bennet, though personally brave and a proven battalion and brigade commander, was unsuited to divisional command due to his almost total lack of diplomacy, low opinion of the regular staff corps and disdain of the British. He believed tanks would be useless in Malaya so didn't even request any, then had his forces routed by a small quantity of generally inferior Japanese armour.
The campaign was run on a shoe string by the Japanese and, unless they were willing and able to deploy far greater forces, it likely would not have taken much to have changed the result.
Rerouting the 2nd AIF 7th Division to Australia instead of Java probably saved Port Moresby, as even if they hadn't been lost in Java, they would never have had time to re-deploy to the battles along the Kokoda Track.
Australia made do with small numbers of quite diverse equipment, in particular aircraft, in the early phases of the Pacific / SEA war.
The British general staff and individuals such as Montgomery, desperately wanted to retain at least some of the 2nd AIF in North Africa and for future use in Europe, as they, like the Canadians and New Zealanders, were very much considered to be elite.
This raises several questions and extrapolated what if possibilities.
Could Singapore have been saved?
What would it have taken to save Singapore?
What would the cost of abandoning Singapore and withdrawing to Australia have been?
What difference would the men and materiel saved have made if employed elsewhere in more defensible locations?
What would it have taken to convince Australia to leave one or more divisions in North Africa?
What would it have been worth to the Allies to retain the 2nd AIF in Africa / Europe?
What forces could Britain have transferred to Australia in compensation for keeping the 2nd AIF?
Could beefing up the RAN, in conjunction with saving the 8th Division have been enough not to need the return of the 6th and 9th divisions?
Once Australia was safe from invasion could the 1st Armoured Division have been available for Europe instead of sitting in Western Australia until disbanded?
Ideas?