Canberra, 13 January 1965
Secret
The Military Situation in Malaysia
Aim
To assess the current military situation in Malaysia and the threat to the area over the next few months. This paper does not take into account the current or future political factors.
The Military Situation
The Borneo Territories
2. Until early December 1964, there were about 10,000 combat troops in Kalimantan (Indonesia Borneo), consisting of three Javanese and eight regional infantry battalions, two parachute companies and two marine companies. Over the past weeks it has become evident that a large reinforcement of Kalimantan is taking place. While our evidence is still incomplete it appears that:—
(a) three brigades are moving from Java into positions in West Kalimantan generally opposite First and Second Divisions of Sarawak;1 a fourth brigade is to be employed in the same area, but we cannot say whether this will be a further reinforcement from some other area or formed from the units which were in Kalimantan prior to the reinforcement;
(b) the equivalent of two brigades, also from Java, comprising infantry and marine battalions, are reinforcing East Kalimantan generally in the area opposite Sabah;
(c) these forces will be deployed and could be ready for operations by about late January/early February 1965.
3. There are signs that the Indonesian Air Force is in the process of redisposing radar units to facilitate operational use of aircraft outside Java. It continues to be used to provide logistic support for forces inside Kalimantan.
4. Some improvement has been evident in Indonesian planning of and preparations for infiltrating groups across the border, but the Indonesians are still faced with formidable difficulties. These include:—
(a) problems of command, communications, supply and mobility, w hich will affect the scope and speed of operations; all of these will be aggravated by the difficult terrain;
(b) the lack of support for raiding parties by local people in most border areas;
(c) the lack of any substantial support in Sabah and Sarawak apart from that provided by the Clandestine Communist Organization, a number of Sarawak Muslims and some of the Indonesian immigrant population in Sabah;
(d) the introduction by Malaysia of the Air Defence Identification Zone under which intruding aircraft are treated as hostile.2
All these problems will also apply to the employment of the regular reinforcements.
The Threat to the Borneo Territories
5. We consider that during the next few months there will be a significant increase in Indonesian military activities against the Borneo Territories. The present build-up of forces is probably intended (in order of probability):—
(a) to intensify the scope of present military confrontation activities, (perhaps in conjunction with increased infiltration against Malaya/Singapore);
(b) to provide a counter-attack or defensive force (Indonesia may foresee that some action on her part is likely to provoke British/Malaysian retaliation);
(c) to provide a show of force with the object of inducing Malaysia to make concessions in order to avoid open war;
(d) to enable Indonesia to conduct large-scale aggression against the Borneo States, the most probable areas being the First and Second Divisions of Sarawak, and Sabah.
6. If, as we believe, it is Indonesia’s intention to step up operations, it is likely that she will attempt to carry out her concept of operations by:—
(a) widespread shallow crossborder raids, probably in company size, to saturate Security Force defences;
(b) deep incursions by regular/volunteer groups of up to company size under cover of (a) above, with the aim of sabotage, terrorism and assassination;
(c) exerting continuous pressure by the threat of invasion through the presence of strong regular formations on the border;
(d) in the event that large-scale aggression is attempted, the simultaneous commitment of up to three brigades against Sarawak and two against Sabah, with naval and air support, presumably after operations in (a) and (b) above have had some success, and probably in conjunction with increased operations against Malaya/Singapore.
Malaya/Singapore
7. During the past six months the Indonesians have built up their base structure in the Riouw Islands and Sumatra which supports the infiltration raids into Malaya/Singapore. This has involved the commitment of more regular troops in addition to the continued recruitment and training of volunteers. Operations have increased in frequency, but not in size, and have been notably unsuccessful to the extent that few major incidents have occurred. Of about 450 Indonesian regulars and volunteers committed in raids about 420 have been killed or captured. About 20–30 infiltrators could still be at large in the peninsula but their effectiveness is likely to be very limited.
The Threat to Malaya/Singapore
8. Despite the known and probable build-up in Sumatra and the Riouw Islands, Indonesia is unlikely to engage in large-scale raids or infiltrations against Malaya/Singapore. While the frequency, number and area of the raids will be increased, Indonesia will seek to avoid retaliation by limiting the strength of any one operation. Indonesia will continue to seek the support of Malaysian dissident groups and the remnants of the Communist Terrorist Organization in southern Thailand.3
Conclusions
9. A significant military build-up is occurring in Kalimantan which presages a higher rate of Indonesian military activity against the Borneo Territories and could lead to large-scale aggression. Indonesia appears to believe that such aggression would only lead to local retaliation. Infiltration raids into Malaya/Singapore are likely to increase in number and frequency and cover increasingly wider areas. However, Indonesia will continue to avoid expanding her confrontation activities in Malaya/Singapore to the point where British/Malaysian retaliation against significant targets in Indonesia would be provoked.
[NAA: A4940, C4024]
1 See footnote 1, Document 228.
2 See Document 162.
3 See footnote 13, Document 136.