Defences of Singapore and Malaya – As assessed by Major General Sir William Dobbie 1935 -1939, GOC, Malaya Command
Defence plans of Singapore and Malaya was solely planned to defend the Naval Base of Singapore when it was decided to be built in 1921.
With a Naval Base in Singapore, sea communications and security east of the Indian Ocean would be controlled by the British Fleet.
Construction began in 1922 and the Admiralty made an assumption to the War Office that a Japanese expeditionary force coming through the Malaya Peninsular would not achieve its objective (Singapore). If the expedition was launched, Japanese shore based supplied aircrafts have to develop airbases close to Singapore and a long sea voyage has to be launched from Japan. This would enable a British Fleet to reach the Far East in time if it happened.
The assumption of command considered that
(1) the probable form of attack would be a landing on Singapore Island under cover of a naval bombardment;
(2) enemy air attack would be carrier-borne and therefore limited;
(3) the enemy would be unable to land on the east coast of Malaya during the north-east monsoon (October to March); and
(4) the difficulty of the country inland was such as to provide an automatic defence for the base from the north.
Major General Sir William Dobbie refuted this assumption when he was GOC of Malaya from 1935. He saw the Malay Peninsula as a decisive point for the defence of Singapore. He reassessed the situation when he assumed command at Singapore in August 1935. By then considerable progress had been made with the fixed defences at the base. The guns were then facing out to sea to repel the anticipated attack from that quarter.
Exercises aimed at testing the feasibility of an enemy landing on the east coast were held during the north-east monsoon of 1936/7. These exercises proved that it was not only feasible to land during the monsoon period, but positively advantageous to the attacker. This was by virtue of the fact that bad visibility limited the defender's air reconnaissance and reduced the efficiency of air attack on the enemy fleet and its transports.
Dobbie wrote to the Chief Of Staff:
...It is an attack from the northward that I regard as the greatest potential danger to the Fortress (Singapore). Such an attack could be carried out in the northeast monsoon. The jungle is not in most places, impassable for infantry.
Dobbie further added:
that an attack might be possible between the months of November and March, despite high winds and waves produced by the northeast monsoon. The recent landing of "5000 smuggled coolies" during this period, dissolved any preconceptions that the monsoon offered protection. On the contrary, this monsoon would provide good cloud cover for the invaders.
Dobbie’s thoughts on forward defence:
I am in any case seeing whether I can dispense with the Battalion of the Federated Malay State Volunteers which is earmarked to come to Singapore as part of the garrison of the Fortress. I can’t help feeling that the security of the Fortress might be better served by having a stronger force in being outside it… I consequently feel that the answer to the possible threat [of Japanese landing and establishing an advanced base on the mainland] is primarily to be found in Suitable mobile forces in being in the Malay Peninsula…
- Major General Sir William Dobbie, 1935 – 1939 GOC Malaya Command, to War Office 17 March 1936
In retrospect, it is almost as though Dobbie scripted the sequence of the Japanese attack in December 1941, which followed precisely his appreciation of what was likely to happen, based on the experience of the British forces during their 1936/7 maneuvers.
Dobbie's Chief of Staff during the exercises was Colonel A E Percival destined to serve as G Percival's finalised report in the late 1937, did confirm that north Malaya was a strategic position for the conquest of Singapore and Borneo. Both Dobbie and Percival made it clear that Singapore could no longer be seen as a self-contained naval base, and that its survival rested on the defence of mainland Malaya.
Dobbie sent to the War Office his appreciation of the likely methods the invader would use.
(1) the securing of advanced air bases in Siam or Indo-China;
(2) landings at Singora and Patani in southern Siam and at Kota Bharu in Malaya;
(3) possible subsequent landings at Kuantan and Mersing;
(4) an advance down the main road and railway on the western side of Malaya with the object of attacking Singapore Island from the north.
Hence, Dobbie proposed a defence line in Southern Johor called the Kota Tinggi Defence line ( Forward Defence system of Singapore Naval Base)He suggested Singapore Fortress defence line improved in 1937. Penang Fortress Defence should also improve. Hence, Penang, Kota Tinggi & Singapore Pill Boxes were similar with the Naval Pill Box design adopted design – related to Naval Defence Plans.
Pill Boxes would be protected by obstacles, backed by road grid of lateral roads. Pill boxes design were not uniform. Location and settings determined how they were built. Some had a tower projecting at the top of the structure for spot lights. These were found on beach and coastal regions to oppose landing and provide anti Motor Torpedo Boats raids over any water. The turret tops were used for observation for artillery and normally had two slots for machine guns. They were of the 1936-1938 Construction types.
GBP60, 000 allocated to construct pill boxes along the Johor River and short way westwards from Kota Tinggi. Roads were built by Rubber Companies at cost price
By 1939, GBP23, 000 have been spent on defences in Johor, Penang and Singapore. Dobbie retired at 60 & Lt Gen Lionel Bond took over as GOC Malaya Command in 1939. He accepted that the defence of Singapore rested on the defence of Malaya and appropriate preparations in anticipation were begun.
However, War office could have cut down the costs of developing the Naval Base in Singapore. Defence works was incorporated in the Defence Scheme Malaya and subjected to approval by the Committee of Imperial Defence & Chiefs of Staff Committee.
Defences work stopped as Malaya was not the only area on Britain's strategic agenda during the period of Lt Gen Sir Lionel Bond command from 1939 to 1941. However, army “economy” type pill boxes were built further north of Malaya in 1940’s as per Dobbie’s assessment and concurrence from Bond i.e. in the East Coast of Malaya to defend against Beach Landings and Airbases and North West of Malaya from Jitra down to Penang – mainly to protect forward aerodromes and attacks from the north.