I was in Singapore earlier this week with Lowy Institute colleagues for a workshop co-hosted with the Council on Foreign Relations. Our theme, highly relevant for Australia, was 'Southeast Asian Perspectives on US-China Competition'. 

After a decade of being seen largely through a counter-terrorism lens from Washington, in recent years Southeast Asia has attracted a broader spectrum of attention in US security, foreign and economic policy circles, as part of the Obama Administration's rebalance to Asia – the theme of our previous collaboration with CFR. 

One immediate question posed was: will the next US president be as focused on the region as Obama was, or at least intended to be? The prevailing view is that Southeast Asia is likely to be kept on Washington's radar by the South China Sea issue, but Southeast Asians are concerned this should not be a new single-issue lens to replace terrorism. We also heard that sustained US engagement would depend not only on a clear enunciation of US strategic interests in the region, but on Southeast Asian states being prepared to put more of their own equities on the line, including in the South China Sea.

Workshop participants widely echoed the linkage of domestic politics to external behaviour as a theme common to all players, including China and the US. The South China Sea didn't dominate the discussion as much as I'd thought. We devoted time to consider how the US and China cooperate and compete in Southeast Asia's growing economic space.

Here, participants agreed that if the Trans-Pacific Partnership is left hanging as unfinished business, the US will take a reputational hit. Politically, Washington has won over Southeast Asia under Obama through its active embrace of ASEAN. But the greatest challenge facing the US is to demonstrate it can economically sustain its stabilising presence in Asia. Regardless of the TPP's real impact, it has become a totem of US engagement and leadership. Reformers around the region who have attached themselves to it will also lose ground without ratification. We heard a perspective that the 'software' approach, exemplified by the TPP, contrasts with China's infrastructure-heavy 'hardware' initiatives in the region, embodied by One Belt One Road and the Asian Infrastructure Investment Bank.

The challenge is that Southeast Asia needs both and shouldn't have to prejudice one over another.

This desire to avoid exclusive choices between the US and China has become something of a mantra in Southeast Asia. We hear echoes of it increasingly in Australia. But not everyone thought it was realistic to expect the US and China to work out a regional role division on security and economics, as the two are inextricable. Economics is still the most likely field for the US and China to cooperate.

We heard that competition isn't all bad either, especially in economics. Southeast Asians are adept at channeling great powers desire for influence to their advantage. High-level attention from China and the US creates opportunities as well as risks. However attached Southeast Asians are to 'ASEAN centrality', there is also a growing resignation that it is beyond Southeast Asia's collective capacity to 'tame the elephants'. Concern about being trampled underfoot has grown now that China's diplomacy toward the region has lost its smile. To coin a Southeast Asian metaphor, the rattan stick is now brandished alongside the durian. 

Some of ASEAN's members have come to doubt whether China really respects its 'centrality'. China's overbearing attitude in recent years may be owed to a 'backyard' mentality towards Southeast Asia, when it should be treating it as its 'front-door' region. An interesting comparison was offered here to the Monroe Doctrine poisoning US relations with Latin America.

Given the intensification of US-China strategic competition in the South China Sea, I was surprised to hear concerns being aired that the US and China might still go over ASEAN heads and strike a 'G2' grand bargain. 

In the South China Sea we canvassed the intersection of law, history and power, and questioned whether the soon-expected Permanent Court of Arbitration ruling in the Hague is likely to prompt a strong counter-reaction from China or lay a legal basis for off-ramps to resolve territorial tensions. My take-away on the South China Sea was that Southeast Asia may not speak with one voice, but the number of voices expressing concern about China's actions has certainly grown. Some take the view that China's interests there are 'existential', though the primary drivers are domestic. The South China Sea links back to ruling party legitimacy – and not only for China. 

In a session on transnational security challenges, we heard that terrorism, human trafficking, internal conflicts and cross-border crime are stubbornly persistent in Southeast Asia, given its diverse physical and political geography. This opens up new avenues for the US and China to cooperate, although widespread corruption means state apparatus in parts of Southeast Asia has been captured by criminal or other vested interests. Terrorism is morphing as ISIS-trained operators move back from the Middle East. US engagement, much of it below-the-radar, will remain important. But counter-terrorism directly involves China too, through the presence of Uighurs in Southeast Asia, a sensitive issue that cuts across counter-terrorism, human rights and geopolitics.

We were obviously tapping the zeitgeist. Just a few days before, Bilahari Kausikan, Singapore's recently retired top diplomat gave a public speech on an almost identical theme: 'ASEAN and US-China Competition in Southeast Asia'. 

I say 'almost' as Southeast Asia and ASEAN, while often used interchangeably, are not the same thing. ASEAN is a regional organisation, in some ways less than the sum of its parts. For anyone interested in a regional policy insider's blunt and caustic take on Southeast Asia's never-ending dance with the major powers, Bilahari's speech is worth reading, or watching. Bonus epithet at 17:19.

Photo courtesy of Flickr user The White House.