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The Battle for Singapore
The Battle for Singapore in World War Two really begins on the 1st of February 1942, when the last British troops have left Malaya and all are bottled up in their 'Island Fortress'. The commanding officer on the British side is General Percival, on the Japanese side it is General Yamashita. The forces either side has available is roughly thus:
Type |
British + Commonwealth |
Japanese |
Men |
~ 140.000 |
~ 30.000 |
Guns |
> 740 + > 2.500 MG |
~ 440 low on ammunition |
Tanks |
- |
18 |
Planes |
? |
? |
Vehicles |
>> 1.000 |
> 3.000 |
On paper, the Japanese have the 18th Division, the 5th Division and the Imperial Guards. The British have the Australian 22nd and 27th Brigades, the Indian 44th Brigade, the 1st and 2nd Malay Regiments and the British 53rd, 54th and 55th Brigades guarding the coast. All that is known of the RAF is that they employed Brewster Buffalo fighters from Sembawang Airfield, planes that were no match for the A6M Zeros. According to my count they had at least 20-30 of these planes. They also used 10 Hawker Hurricanes later on in the war.
The battle will be described day by day, starting even before the outbreak of hostilities in the Pacific. This will, I hope, aid in clarifying the situation.
In October 1941, there was a summit meeting of British and Australian officials regarding security. Among those who attended were: Britain's Commander-in-Chief, Far East, Air Chief Marshal Sir Robert Brooke-Popham, the British Government's special envoy to the Far East, Sir Alfred Duff Cooper, Australia's representative to the British War Cabinet, Sir Earl Page, Britain's ambassador to China, Sir Archibald Clark-Kerr, Straits Settlement Governor, Sir Shenton Thomas, Britain's Commander-in-Chief, China Station, Vice Admiral Sir Geoffrey Layton.
On the 8th of December, Singapore is first hit by a Japanese air raid. 27 Japanese bombers attack the Keppel Dock installations, but also hit Raffles Place at around 3:30 am. 64 people die, over 100 are wounded.
The first reaction on the part of the authorities is to impose severe censorship, with the goal of preserving public morale. The reports of air raids on Singapore published in The Straits Times are very brief indeed. In the following weeks, air raids become sporadic but steadily increase in strength as the Japanese capture more airfields in Malaya and come closer. Among the most often hit targets are the airfields at Tengah, Sembawang and Seletar, the Naval Base and the Keppel and Tanjong Pagar docks. Civil defence measures are extremely insufficient. Large air-raid shelters are not build for the erroneous reason that Singapore's soil is too sandy. Their replacement are shallow slit trenches dug into parks and along roads. They are flooded the first time it rains and rendered unusable. By the middle of January, the Japanese bomber fleets had reached sizes of up to 108 aircraft. The reasons why the Japanese air raids are quite to effective are mainly two. For one thing, the British were confident that the Japanese were unable to fly (this was actually said at the time) and the city was not (rpt not) darkened. It was kept with all the lights on and life going on as usual. The Japanese pilots could probably hardly believe their eyes when they saw it! Another reason was the the British had AA guns that could not reach the standard altitude of the Japanese bombers. Two things, that, when added together, give a very bad combination for the British.
On the 20th of January, Winds Churchill sends a message to Allied Supreme Commander General Wavell which includes a 10-point plan for the defence of Singapore. The plan calls for pressing the entire male population of Singapore into work gangs for building defensive works along the northern shore of Singapore. On the next day, Churchill sends the following message to Wavell regarding Singapore: "I want to make it absolutely clear that I expect every inch of ground to be defended, every scrap of material or defences to be blown to prevent capture by the enemy, and no question of surrender to be entertained after protracted fighting among the ruins of Singapore City." It strikes one that this is not at all unlike the idiotic hold-to-the-last-man orders Hitler gave so frequently.
About four weeks earlier, (quote from 'Defence Plan for Singapore, Media Master's WW2 Battle Guide) "the Chief Engineer of Malaya Command, Brigadier General Ivan Simson tries to persuade Percival to begin constructing defence positions in Singapore before it's too late. Percival, seemingly over burdened by the awesome resposibilities of the northern campaign that is going so badly for him, is incapable of comprehending the gravity of Simson's urgings. The engineer argues that he has been sent to Malaya Command for the precise purpose of ensuring that adequate defence works are undertaken. He points out that whatever static defences there are - arbed wire beach entaglements, minefields, concrete machine-gun pill-boxes, gun emplacements and the like - are all guarding against a long percieved Japanese seaborne invasion from the south. Clearly this is a major miscalculation that needs rectifying. Simson talks of a crash programme to introduce beach defences along the islands's northern coastline combined with patterns of fixed positions in depth at points considered the most likely targets for Japanese assaults across the Straits of Johore.
Amazingly, Perical is unmoved. Simson refers to fallacious but still widely held views in Britain of "Fortress Singapore" being somehow impregnable [much like today everybody holds 'Fortress England' to have been impregnable in 1940]. He remarks that a fortress without defences represents a dangerous contradiction in terms. Percival's eventual reply stuns his Chief Engineer: "Defences are bad for morale - for booth troops and civilians." So Singapore is deprived of its northern defences.
When Wavell flies into Singapore on January 20, Percival is struggling with his plan for the island's counter to an imminent Japanese siege. During discussions between the two senoir British officers it becomes clear that Percival believes the initial thrust of the Japanese assault will come down the Johore Riber from the north-east, across the Straits of Johore, and strike in the Changi area [guarded by the British 54th Brigade and the 2nd Malay Regiment]. Wavell, on the other hand, feels the greatest danger is in the north-west and instructs that the British 18th Division be positioned in this region of the island. He considers these troops to be the freshest, least battle-mauled available. Ultimately, Wavell defers to Perical's campaign experience and gives his commander final discretion on all troop deployments.
Percival's defence plan is completed on January 27 and rushed late that afternoon to the three generals he has chosen to make the battlefield decisions at the final showdown. The plan divides Singapore into three broad fighting sectors - Southern, Northern and Western - with a central reserve area controlling supplies.
The Southern sector, to be commanded by Major General Keith Simmons, will comprise the 1st and 2nd Malay Infantry Regiments, the Straits Settlements Volunteer Force, Fortress troops and fixed defences. Its area of responsibility will stretch from the Jurong River mouth to the south western coatline, eastwards to include the Keppel Docks and harbour, the Singapore business area, Kallang airfield and on to Changi. Also within this sector's tacitcal control are the southern islands of Blakan Mati (now Sentosa), Pulau Brani, Pulau Bukom and those to the north east., Pulau Ubin and Pulau Tekong. The 2nd Malay Infantry Regiment will be responsible for the easternmost sector of the northern frontline incorporating Changi.
Northern sector's commander is Lieutenant General Sir Lewis Heath who will lead 3rd Corps now comprising the newly arrived British 18th Division, the Indian 9th Division and the remnants of the Indian 9th Division. This sector's front extends from Changi in the east, in a north-westerly direction along the shoreline of the Straits of Johore to a point half a mile short of the Causeway. Within the Northern sector's command responsibility are the Naval Base and the two most northerly airfields, Sembawang and Seletar.
Chosen as commander of the Western sector is Major General Gordon Bennett, commander of the Australian Imperial Forces (AIF). His units include Australia's 22ns and 27th Infantry Brigades and the untrained Indian 44th Infantry Brigade which arrives in Singapore only on Januarry 22. Western sector's front starts just east of the Causeway and follows the island's northern coastline westwards right round to the Jurong River, a distance of some 18 miles (28km). Almost in the centre of Western sector is the important Tengah airfield. Running south from the Causeway across the sector is the vital Bukit Timah Road, the key land link between Singapore and Malaya.
The critical sector will become ultimately the main target of the Japanese landing. What is more, the Australian troops here, stretched along 11.3 miles (18km) of shoreline, most of it mangrove swamps, will face the initial onslaught alone.
The Western front is divided into three sectors, two of them manned by Australian troops, the third by Indian. On the right the Australian 27th Brigade is given what is called the Causeway Sector measuring 4000 yards (3670 metres) from just east of the crossing point westwards to the Kranji River. In the centre of the north-western sector is a front of some 16000 yards (1467 metres) running from the Kranji River west to the Berih River. This is manned by the Australian 22nd Brigade. Finally, on the left, the Indian 44th Brigade is in charge of the south-western sector reaching from the Berih River around to the Jurong River.
The Reserve Area is led by Brigadier General A.C. Paris, commander of the Indian 12th Infantry Brigade. Within his perimeter are the MacRitchie and Pierce reservoirs, and the huge food, fuel and ammunition dumps scattered throughout the centre of the island, particularly around the Bukit Timah racecourse."
On Jauary 31, the British finally pull out of Malaya and are besieged on Singapore.
February 1: Percival informs the island via radio that it is now in a state of siege. He holds conferences with his staff, which all concern demolition work in the Naval Base and the defence of Singapore. Meanwhile, the troops delegated to defend the northern shore man their positions and frantically begin constructing make-shift fortifications.
Yamashita moves his HQ south to Kluang and outlines his own plan to capture Singapore. The plan is roughly thus: The 5th and 18th divisions assault the island's north-western shoreline. The Imperial Guards make a diversion in the east, leading the British to believe that Changi is the goal of the attack. Nashimura, the commander of the Imperial Guards, bitterly complains that his troops are being given a second-class job and vehemently insists that he be given the main thrust. Yamashita ignores him.
February 2: Eight major Japanese air raids target Singapore throughout the day, notably striking the Naval Base's oil storage tanks. Smaller air raids also target the Tanjong Pagar railway station with incendary bombs.
February 3: All the Australian commanders are in agreement that their lines on the shore are too weakly manned.
The Japanese evacuate all civilians in a 12-mile distance from the Straits of Johore. They build multiple positions for their artillery and ready over 3000 vehicles and landing craft for the invasion. Yamashita is handed an intelligence report according to which the British are planning to release the remaining oil in their tanks onto the Straits of Johore on an incoming tide and turning the Straits into a river of fire. Yamashita orders the oil tanks to be destroyed with artillery.
Japanese troops also send two swimmers across the Straits to gather intelligence. They return two days later with highly accurate maps of the British/Australian positions.
February 4: Japanese artillery targets the three northern airfields (Tengah, Seletar and Sembawang) as well as the Naval Base's oil tanks. The airfields are abandoned within 36 hours, everythin serviceable being moved to Kallang airfield.
The Japanese put lookouts in all tall buildings in Johore as well as in balloons. Using these observers, they are able to target artillery and bombing missions with great accuracy. This means that Allied troops can only move at night.
February 5: Nishimura once again requests to be made part of the main effort. Yamashita ignores his request again. Japanese artillery targets the northern shore but also the centre of Singapore itself.
A convoy of three ships enters port, bringing with it the rest of the 18th division. A fourth ship was hit by Japanese dive-bombers and sinks. Prompt action by the Royal Navy saves almost all the soldiers.
Percival is optimistic about a three-month siege with a relief force coming then.
February 6: Yamashita holds a final meeting before the attack. He orders the attack to begin on the 8th at 10pm. Nishimura distrusts Yamashita's strategy and cannot be moved even by a friend who tries to negotiate between the two. Yamashita moves his HQ to the Sultan of Johore's Palace in Johore. He is now 1 mile away from the Australians, who know nothing of his presence.
Japanese artillery shells the eastern part of the island in an attempt to make Percival think the landings will come in the Changi area.
The Australians send two five-man teams across the Straits of Johore in small boats during the night to report on Japanese troop concentrations.
February 7: The Australian teams come back and report on well-camouflaged Japanese gun positions and all signs of a coming invasion. A senior officer of the 22nd Australian Brigade calls Malaya Command to warn them that the Japanese attack is due against the Australian lines at any moment. Malaya Command considers that Japanese troop movements at Pulau Ubin (in the east) are more important.
After nightfall, the Imperial Guards move 20 collapsible boats through the jungle and cross over to Pulau Ubin in them. Before midnight 400 officers and men with two mountain guns of the Imperial Guards have taken control of the granite island overlooking Singapore.
February 8: Japanese artillery and air strikes target the British and Australian command and control facilities with extremely good accuracy. Some are destroyed, others forced to move. More reports arrive on the Japanese positions and the Australians are ordered to shell them with artillery.
Japanese artillery bombardment slowly moves to the north-western shoreline and continues there in full strength. It reaches a crescendo at 7 pm. By this time, lines of communication are practically non-existant, the troops are cut off from their respective HQs.
The 5th and 18th Divisions embark from their well-camouflaged positions. Each division has 15 motor launches and 100 collapsible boats as transport. The first wave has 4000 men. At 7pm the boats are launched and the troops get in. The engines are started and at 8pm the boats cautiously move towards the Singapore shoreline.
At 8:30 pm an Australian observation post notices the boats and reports. Orders are given to hold fire until the invaders are 50m away from the shore. Only seconds later, however, Australian machine gunners open fire. Some of the boats sink, others overturn and capsize. The Japanese move further west to look for a weaker spot in the defence line. Some are quickly found and the Japanese land in various places. Violent fighting erupts with heavy casualties on both sides. The Australians withdraw and by midnight the 5th Division has driven a wedge between the 22nd and 27th Australian Brigades.
The 18th Division was able to land with almost no problems, perhaps due to more cock-ups in the British lines of communication. They can land in strength near the Berih River and prepare to thrust towards Tengah airfield.
Yamashita also has no means of communicating with his troops. He is forced to watch from the Sultan's palace. Around midnight, a red and a white signal shell detonate over the landing zones of the 5th and 18th Division. The invasion has been a success. It is reported that the officers in the palace had tears running down their cheeks when they saw this.
February 9: Yamashita stays awake until 4am the next morning (10th). Then he feels the entire operation will be successful.
The British and Australian lines of communication are still in chaos. Almost no reports come in until midnight-1am. The only reserve the Australians have is sent to the front.
A bit later, the commander of the 22nd Australian Brigade, Brigadier General Taylor, plans a counter-attack but when he realises that the Japanese are 200m from his HQ, scraps these plans and evacuates the HQ with the intention of forming a defensive line further inland.
Around 7am ten Hurrican fighters take off from Kallang and battle the 86 Japanese planes over Singapore. 6 Japs and one Brit are shot down. The RAF makes two more fighter sorties, then all planes are evacuated to Sumatra.
The 12th Indian Brigade (consisting of 400 Argyll and Sutherland Highlanders, 150 Royal Marines and 440 4/19th Hyderabad Infantrymen) is sent to join the fray when Percival finally realises that the invasion has commenced in full strength. A general regrouping of forces in the west is ordered.
During the afternoon, the 5th Division captures Tengah airfield after heavy fighting.
Percival is starting to panic and is already planning the final defense line, which will incorporate the city and the vital water reservoirs.
February 10: Nashimura, in an attempt to get his own back on Yamashita, delays ordering the Imperial Guards to cross the Straits and attack the Australian 27th Brigade between Kranji and the Causeway. The result is that his troops get stuck on a low tide. Many boats strand, others move into tributaries, some unload troops into deep mud or mangrove swamps. Oil, seeping out of the destroyed Naval Base's tanks, catches fire and many of the Japanese burn to death. Australian machine guns and mortars open fire on the landing force. Nashimura panics and asks Yamashita for permission to call off the attack. Yamashita will have none of it because that would jeopardise his entire plan of battle and orders Nashimura to do his duty. The situation seems hopeless, only suddenly, through a misunderstanding of orders, the Australians suddenly begin withdrawing. The Australians keep on withdrawing to the utter amazement of the Imperial Guards, who are now able to land large numbers of troops and pursue them relentlessly. They are able to take Woodlands and the high ground overlooking the Causeway.
Yamashita has crossed the Straits himself and is on the island.
27 Japanese aircraft bomb Malaya Command, destroying part of it and nearly killing Percival and Wavell, who has flown in for a visit.
Taylor mistakes orders passed on from Percival concerning the last defence line and thinks these are orders to proceed there immediately. He withdraws, and the troops bordering on his are forced to withdraw also. The Indian 44th Brigade's forward patrols meet with Japanese troops further along the Kranji-Jurong line, and fighting erupts. Seemingly without reason, the entire brigade is suddenly in full retreat. The officers can no longer control the men. Eventually, the 44th is rediscovered four miles south of where it should be.
The Kranji-Jurong line must be given up before the Japanese were even able to attack it.
Towards evening, Japanese tanks make their first appearance. As bas as the Japanese tanks were when compared to other tanks, they throughly routed the defenders here. They smash their way through two spontaneous counter-attacks and seem about to crush the defence of Singapore altogether when they suddenly stop and switch their engines off. The crews has accomplished their assigned mission and had decided to call it a day.
In Government House, Wavell remarks that he had always wanted to relieve Percival and that 'it shouldn't have happened!'
February 11: It is 'Kigensetsu', Japanese National Day, the day on which Yamashita wanted to be in possession of Singapore. He isn't, and he doesn't much like it. He has 20 messages to Percival demanding surrender dropped over the city by planes. The Japanese 5th Division has executed a very successful night attack and is now in control of Bukit Timah Village. The fighting included bayonet charges and hand to hand combat. Losses in the Australian 22nd Brigade are extremely high.
The Japanese continue the advance on what the British depend on. The Imperial Guards force their way through the Australian 27th Brigade and the remains of the Kranii-Jurong line, heading for the water reservoirs. The 5th Division with its tank support drives on towards the massive food depots.
All HQs are on constant retreat, moving further and further south into the city centre. It is also reported that thousands of soldiers are deserting and seeking shelter in city buildings.
The Japanese repair the Causeway and start moving troops and supplies over it. The British abandon the Naval base and retreat south to the Sembawang airfield.
A cargo steamer leaves Singapore, overfull of refugees, most of them military nurses.
February 12: A good day for the defenders. All attacks can be halted or thrown back. Even the tanks, charging down Bukit Timah Road, were stopped by British anti-tank gunners. The Japanese suffer heavy casualties all-round.
Percival decides it is time to withdraw to his final defence perimeter. The Australian command is in chaos as personal hatred between the two commanders comes to a head and one the commanders faints from lack of sleep.
A British gun standing in the garden of Government House draws unwelcome attention to the place. It is shelled and bombed.
February 13: Yamashita moves his HQ to the Ford Motor Factory. He has recieved intelligence reports of Indian, Australian and British troops busy digging themselves in and realises that Percival is hoping to lure the Japanese into street fighting. Yamashita has neither men nor ammunition for such a battle. He further believes that the British are expecting a major relief convoy and tells the Navy and Air Force to keep a special look-out. Yamashita's only hope, as he sees it, is to attack before the British can fortify their positions. He orders a two pronged attack. One prong is the 18th Division, heading for the Alexandra barracks, the other are the Imperial Guards who are supposed to capture the reservoirs. Nishimura however decided not to move his men. Repeated instructions from Yamashita are neccessary to make him obey his orders.
On Buit Chandu (Opium Mountain) the 2nd Malay Infantry Regiment makes an epic 48-hour stand. Even though the defence line around them is crumbling everywhere, they hold their positions until they are killed almost to a man.
Percival opens a meeting beginning with the opinion that the fighting must continue irrelevant of the situation. Nobody agrees with him. He is urged to surrender. Percival orders the fighting to continue and asks Wavell for orders. Wavell tells him it is in the 'wider interests' of the war against Japan for him to continue fighting.
The Governor of Singapore, leaving his now uninhabitable home, realises how large the problem of desertion is. He sees "gangs of armed deserters" in the streets begging for food.
February 14: The Japanese attack goes better. The Imperial Guards have already taken the last water reservoir and are pressing on. The 18th Division also continues the advance. Once again Japanese tanks make a charge that cannot be held back until it is stopped by AT guns again. The Japanese Air Force has increasingly changed from tactical bombings to terror bombardment of Singapore itself.
Percival is told by his chief engineer that water failure is imminent. Hardly surprising seeing that the Japanese hold all the reservoirs and the pipelines were destroyed in the retreat from Malaya.
All estimates agree that with one million men confined within three miles, water reserves can hold at most 24 hours and epidemics seem impossible to avert seeing that there are many dead and it is impossible to bury them. Percival once again asks Wavell for permission to surrender. Wavell replies that the fight must go on: "Your gallant stand is serving a purpose and must be continued to the limit of endurance." Not unlike Hitler's arguments on the subject of holding positions.
Japanese troops capturing Alexandra Hospital massacre patients, doctors and nurses. Almost 200 people die.
The Australians manage to capture exact copies of Yamashita's final defence plans. They are translated by a Japanese-speaking officer, who tells Malaya Command their content. However, he feels there is only 'academic interest' in what he is saying.
February 15: Again, the Japanese have made successful night attacks. Percival, when asking for a report on the situation hears roughly this: Food stocks will last for 48 hours, water stocks at most for the next couple of hourse. AA ammunition is depleted, artillery ammunition is almost. Small-arms ammunition is available in reasonable quantities. All the available fuel is in the tanks of vehicles. Percival feels there are only two ways to go from here. Either make a counter-attack and recapture the MacRitche Reservoir or surrender. Everybody says it is impossible to counter-attack.
Shortly afterwards, a white flag is hoisted on the broadcasting studios at Caldecott Hill. This is reported to Yamashita, but when a truce delegation wishing to see him is reported at 2pm, he refuses to see them saying he will deal only with Percival himself.
At 5:15 pm, Percival meets Yamashita at the Ford Factory with two staff officers and an interpreter. Six other Japanese officers and a good amount of war correspondents and journalists are present.
Yamashita: Do you wish to surrender unconditionally?
Percival: Yes - we do.
Yamashita: Have you any Japanese prisoners of war?
Percival: None at all.
Yamashita: Have you any Japanese civilians?
Percival: No. They have all been sent to India.
Yamashita: Very well. Will you please sign this document of surrender??
Percival proceeds to study the document. At approximately the half-way point he pauses and asks: Would you wait until tomorrow morning?
Yamashita (angrily): All I want to know is do you surrender unconditionally or do you not?
Percival reportedly became pale and began a dialogue with Yamashita's interpreter.
Yamashita (shouting): Yes or no!
Percival (quietly): Yes.
And that's that. The Impregnable Fortress Singapore is fallen. Did it have to?
I asked this question on the Heavy Metal Forum and was surprised by the answers. According to them, Singapore was doomed as soon as the Japanese invaded Malaya. I favour a rather different view, having researched the battle pretty well and having visited just about all of the places where decisive fighting took place.
As anybody can see, the entire battle for Singapore was a farce. The British made every mistake possible, there was every foul-up imaginable. The Japanese on the other hand had perfectly accurate intelligence and Yamashita staked everything on one huge gamble. I think this is one of the most well-fought battles in World War Two. Outnumbered heavily and still victorious.
But the outcome does not have to be that the Japanese win. Come on, the battle is so impossible that it almost seems like fiction! Let's start at the beginning: Way back in the middle of the Malaya campaign, Percival could have ordered fortifications to be built in the north, if not on the beaches then a bit behind. There was enough time to do this, even enough time to build concrete machine gun emplacements and possibly even enough time to transfer a few of the lighter guns from the forts in the south. The northern coast could have been turned into just an impregnable beach as the southern coast.
Even if that doesn't happen, the order not to fire until the Japanese had closed to 50m could always have been issued earlier and consequently actually carried out. The first thrust of the 5th Division would have been a disaster. Maybe up to half the boats would have been destroyed, if the beach was properly fortified maybe even more. The remainder could land their troops in the holes in the Australian lines, but the troops would be extremely weak and the Aussies could probably handle them. The 18th Divison might land as planned, but imagine the terrible mistake with the Imperial Guards - withdrawing when the landing force was on the verge of being wiped out - didn't happen! The bridgehead would have been crushed, the boats largely destroyed. There would only be one hope for Yamashita - try to use the 18th Division to secure more landing zones and try to ferry the rest of the 5th Division and the Imperial Guards to the 18th Division's landing site. This would be possible, but very difficult. Especially seeing that he would have - at most - 200 boats left. The only alternative would be to muster 100 boats and try another night-time invasion closer to the Causeway - in the same area where the Imperial Guards would have been defeated earlier.
If the latter works, the invasion of Singapore might at least succeed. The Imperial Guards would fight their way to the Causeway, have it repaired and now resupplying becomes easier. The 18th Division is still cut off from the Causeway, though. The Australians are in the way.
If I were Percival, I would, having realised that the Japanese have comitted all the troops they have to the fight, try to grip the 18th Division's flank with the 44th Indian Brigade and send the 12th Indian Brigade into combat against it as well. The Australian 22nd Brgiade helps on the other flank. The 27th Australian Brigade would try to make some heaway against the Imperial Guards, at the very least try to contain them. I would then send the 53rd and 55th British Brigades to crush the Imperial Guards at their bridgehead. Adopting the same technique as Yamashita, I would order my artillery to fire at full blast in support. I would also order all my planes into the air to support the ground effort or to destroy the Japanese planes.
There would still be a few destroyers left over from Force Z left in Singapore, and I would order these to sail into the Straits of Johore and attempt to disrupt resupply of the Japanese. It might fail and the ships might soon become prey to dive bombers. If not, the 18th Division's bridgehead would be destroyed very quickly, if not it would take a while longer, but not very long. Fighting the Imperial Guards, who would by now be on Singapore in strength with parts of the 5th Division coming over as well would face serious opposition. Troop strength would be equal.
Yamashita should now concentrate on enlarging that bridgehead and would direct all the troops he has left to it. In addition, the Imperial Guards on Pulau Ubin and the surrounding are would probably make a landing in rgw Sembawang area, in the rear of the 53rd and 55th British Brigades.
I would now commit the last reserves to the fight. The 54th British Brigade would try to contain the Imperial Guards at Sembawang, the 1st and 2nd Malay Infantry Regiments would move north to help against the Causeway. The Causeway would, needless to say, be under continuous artillery bombardment. The pocket of the 18th Division's landing sites would now be removed, freeing up more troops for the battle of the Causeway.
Very probably, Yamashita would blow up the Causway again and retreat back to Johore. The invasion would have been a complete and utter failure. I would estimate this to happen at around the 15th of February, thus my artillery and anti-aircraft ammunition supplies look pretty desperate. However, Yamashita's supply of artillery ammunition is even less.
British engineers could do more thorough demolition work on the Causeway and the troops could return to their defensive positions. Losses on both sides would be huge. I estimate about 10 000 - 20 000 on each side. But Yamashita only had 30 000 to begin with. The Japanese must now not only wait for new ammunition, new landing craft and new supplies but also desperately need more troops. And they have very few to spare. At the same time they are invading the Dutch East Indies and Burma.
By the time they assemble as many men as Yamashita had to begin with, which would take about three months, Percival would have been resupplied by British convoys sailing from Egypt and India. The RAF would still be active in Singapore, in fact it is quite possible that additional wings from Java and Sumatra are deployed to Singapore as well. If the RAF managed to acquire control of the air at Singapore (a relatively big if, but not too big), convoys would be able to sail with relative safety.
The Japanese could no longer hope to conquer Singapore. Instead they would be hoping against hope that their troops in Johore will be able to prevent the British from recapturing Malaya. They would divert more troops from Burma to Johore; leading to sooner success of the British in Burma.
In short, the Japanese attack on Burma would be severely impeded, and be beaten back a lot easier and a lot earlier by the British than it was historically. Britain would be able to take control of Malaya again by 1943 or 1944 at the latest. From there they could start putting additional pressure on the Japanese - maybe start their own invasion of the Philippines or simply move north-east via Thailand, French Indochina and China itself.
The war against Japan would not have ended sooner, at least not probably, but it would have spared over 130 000 Commonwealth soldiers the unenviable stay in Japanese POW camps (we all know the stories don't we?).