The Malay word for “neighbourhood”, kejiranan, not only implies a geographical “quarter” or “precinct” but also, in a more communal sense, an interdependent society of individuals and interests. Singapore’s immediate neighbourhood, held together by both history and proximity, contains three states whose relations have been complex at best, and contentious at worst. From the — political and personal — tumult of separation, through the violence of Konfrontasi and the trials of early cooperation, the intrigues which have shaped the attitudes of Singapore, Malaysia, and Indonesia toward each other are often murky to their own inhabitants and impervious to the outside observer. Yet, in addition to hosting the world’s highest cargo traffic in their ports, the three form the core of many new security initiatives in the Asian-Pacific region, and front a region of increasing political salience in today’s world. This essay explores Singapore’s relations with Malaysia and Indonesia through the administrations of three Prime Ministers, whose approaches to Singapore’s immediate neighbours reflect a continuity of outlook tempered with strategic and personal adaptation. While the key influences through five decades of their leadership were, undoubtedly, the three state’s underlying bilateral complexities coupled with momentous changes in Southeast Asia’s broader security context, each Premier also brought a sense of his own style and convictions to the role, which lent Singapore’s foreign policy under each administration a flavour distinctive to its time. Thus, rather than presenting a straightforward assessment of whether Singapore is more secure today than before, and keeping to the theme of this collection of essays, this chapter will explore the new and old security perspectives of each administration in relation to its closest neighbours.

History, geography and demography have condemned Singapore, Malaysia and Indonesia to be permanent neighbours. This geopolitical relationship is often framed in the context of ASEAN Kecil or the Small ASEAN. In turn, this has had serious security implications for the “Malay World” neighbours’security, leading many to describe the triangular relationship as one of security indivisibility and where the three states are seen as the “ASEAN core. Yet, in different ways, each is also concerned with the security dilemma brought about by developments across the borders of the three states, including military modernisation and internal conflicts. While there are many facets to the triangular relationship, it would be far more useful to analyse the bilateral relationships, namely, Singapore–Malaysia, Singapore–Indonesia and Malaysia–Indonesia, and how these have  affected ties among the three states. In general, despite being inseparable from various geopolitical and geostrategic dimensions, relations among the three states have shifted from the initial turbulence, best evident from Confrontation (1963–1966), to one that is defined by intense cooperation, both bilaterally and multilaterally through ASEAN. Still, there are many hiccups in bilateral ties that often sour relations and in turn affect the wider regional security climate.

This article examines the barter trade crisis between Singapore and Malaysia from October to December 1965. Singapore separated from Malaysia on 9 August 1965 after acrimonious relations during the merger period. After the separation, both parties experienced difficulties in their relations with each other, which at times led to tensions. Singapore's attempt to resume barter trade with Indonesia immediately after the separation drew a sharp response from Malaysia. Drawing on archival materials, this article examines the events surrounding the barter trade crisis, an under-researched area within the literature of Singapore's defence policy and history. The barter trade crisis was significant because the Malaysian political leadership had clearly and unequivocally declared their intent to use military force against Singapore for the first time since the separation. As a result of the Malaysian military threat, Singapore abandoned the barter trade proposals. The event arguably left an enduring impact on Singapore's threat perceptions against Malaysia. © 2022 The University of Queensland and John Wiley & Sons Australia, Ltd.