The US has been involved in Southeast Asia for a long time. During the Cold War, the region assumed considerable importance as a theatre for countering the strategic threat emanating from the USSR.  However, American interest in this part of the world waned after the collapse of the Soviet Union as more pressing hotspots emerged in Western Europe, the Middle East and Northeast Asia.

All that began to change with the election of President Barack Obama, who entered office committed to winding down US military engagements against the Taliban and Sunni jihadists in the Middle East. Early in his administration, he announced the so-called ‘Asia rebalance’—a reorientation, that became official policy in January 2012 with the release of a new Defense Strategic Guidance.

This so-called ‘pivot’ explicitly recognises the need for America to re-embrace partner nations in Asia, leveraging their significant and growing capabilities to build a network of states that nurtures, strengthens and sustains a rules-based order that’s capable of effectively addressing regional challenges.

In this context, the US has pursued four main areas of cooperation as part of its bilateral and multilateral engagement with Southeast Asia:

• supporting the development of the ASEAN Community, which was formally launched at the end of 2015
• buttressing defence reform and restructuring
• facilitating humanitarian assistance and disaster relief operations
• providing assistance to address transnational terrorist and criminal threat contingencies.

To be sure, this functional and programmatic engagement is indicative of ASEAN’s increasing importance as a unified collective bloc, the frequency at which large-scale natural disasters affect this part of the world and the existence of a wide range of mutually concerning trans-regional security challenges. However, it’s also very much related to Beijing’s growing power in the wider Asia–Pacific and, more specifically, to heightened Chinese assertiveness in the South China Sea (SCS) and the concomitant threat that this is seen to pose to freedom of navigation in a critically vital maritime trading and energy corridor.

Has the rebalance worked? In one sense it has, by providing the US with both institutional (ASEAN) and geostrategic/ geographical (invested partner nations, basing options) opportunities to balance and offset the rising regional influence of the People’s Republic of China (PRC).

However, a case could also be made that growing American involvement in Southeast Asia (and the Asia–Pacific as a whole) might merely serve to encourage an already paranoid Beijing to adopt increasingly aggressive policies for protecting its self-defined national interests. Moreover, it could be argued that the rebalance has lacked substance, at least in terms of balancing the PRC. While Washington has engaged in a multitude of activities in Southeast Asia, how much these strands have deterred aggression and mitigated attempts at coercion by Beijing is questionable—particularly in regard to the SCS disputes. Here there doesn’t appear to have been any genuine effort on the part of Beijing to resolve ongoing territorial disputes with the Philippines, Vietnam and other claimants. By contrast, the PRC has taken an increasingly belligerent stance, undertaking highly contentious unilateral actions to consolidate and solidify control over all the territories behind its so-called nine-dash line. In this light, a tenable charge could be made that the pivot has largely failed to ensure the emergence of a China that acts as a ‘responsible stakeholder’ in underwriting and buttressing the existing regional order.

Issues of effectiveness aside, perhaps an even more fundamental question is whether the US will continue with its current ASEAN-centric policy as part of a broader program of Asian engagement. Indeed, in an election year that might see a non-Democratic president returned to office, Washington’s priorities may well change and return to a concerted focus on contingencies in Europe and the Middle East. Even if partisan politics doesn’t ‘unbalance’ the pivot to Southeast Asia, fiscal constraints could. Cuts to the defence budget could make the type of large-scale investment needed for underwriting a robust forward presence in Southeast Asia simply untenable.

Assuming that the rebalance survives, it’s clear that a central challenge will be convincing China that the return to Southeast Asia isn’t a thinly veiled strategy of Sino-containment but, rather, an effort to revitalise and strengthen partnerships in a key part of the world. To achieve such an outcome, it would seem that there’s a realistic potential to cooperate with China in the areas of HADR and transnational security as a means of providing the necessary level of confidence to deal with the more sensitive issue of claims in the SCS. More specifically, Washington should impress on Beijing that the two governments share a common need for cooperation to deal with an array of global threats—including many of the cross-border challenges that are manifest in Southeast Asia—and that this would be harder to effect (with deleterious consequences for both parties) in an environment of sustained regional power competition.

Achieving such an outcome will require a nuanced and agile strategy that couples engagement with balancing. The optimal and most sustainable outcome will be the emergence of a regional order that promotes risk-averse behaviour by Beijing and insulates against the type of unilateral action that could quickly escalate out of control to threaten American and local allied interests.