On The Radar: The Iran War & ASEAN

For decades, the United States has been the dominant security guarantor in the Indo-Pacific. That status is now under serious strain - eroded by an unpredictable trade posture, a war in the Middle East that keeps spilling eastward, and a growing sense across Southeast Asia that Washington simply cannot be relied upon.

The latest brinksmanship over US “deadlines” on Iran went past just a few hours ago, with the White House pulling back from threats of the “complete destruction” of Iran’s critical civilian infrastructure such as power plants. As a negotiation tool such deadlines are virtually useless, and only serve to reinforce the perception that Washington doesn't have a workable solution to ending the conflict.  

However, the evidence from ASEAN is far more striking. According to the annual State of Southeast Asia Survey, released this week by Singapore's ISEAS-Yusof Ishak Institute, 29.5 per cent of regional respondents now expect their country's relationship with the US to worsen - more than double the 14.2 per cent who felt that way just a year ago. Meanwhile, only 42.7 per cent of respondents expressed confidence in America as a strategic partner and security provider, down from 44.9 per cent previously.

The survey draws on 2,008 responses from academics, public servants and private-sector professionals - people with the ear of governments across ASEAN.

In a result that would have been unthinkable even last year, most respondents - 52 per cent -said they would choose China over the US if forced to pick between the two.In 2025 the same question produced the opposite result, with 52.3 per cent favouring Washington. That reversal illustrates a significant shift in regional sentiment.

Ms Joanne Lin, Senior Fellow at the ASEAN Studies Centre at ISEAS and one of the authors of the report said: “What stands out in this year’s survey is that Southeast Asia is uneasy about both major powers, albeit in different ways. The region continues to value strategic autonomy and diversified partnerships, but it is also becoming more conscious of ASEAN’s own limits. The broader message is that Southeast Asia still wants balance, not alignment—but preserving that balance is becoming more difficult.”

The Middle East Comes to Indo-Pacific

The survey was conducted between January and late February, before the Iran-US war fully escalated. What's happened since has only deepened the anxieties it captured.

The conflict - centred on US and Israeli military action against Iran - was described by President Trump as a "short-term excursion." It has proved anything but contained.

Iran has mined the Strait of Hormuz, through which an enormous proportion of Asian energy supplies flow. The Philippines declared a national energy emergency last month. Vietnam is seeking help from South Korea and Japan, South Korea is planning to burn more coal and rely more on nuclear power. The energy security that has allowed decades of Asian growth is suddenly looking precarious.

Iran has also carved out a pointed exception to its disruption campaign: China. Beijing is reportedly purchasing up to 90 per cent of Iranian oil exports, while Washington's partners scramble for alternatives and attempt to navigate the latest utterances from the White House.

Trump's response has been to demand that Asian nations - including China, Japan and South Korea – send warships to help reopen the Strait. None have agreed. Japanese Prime Minister Sanae Takaichi pledged vague "security support" during a White House summit, although this was perhaps more appeasement, than commitment.

The war is also exposing security gaps. US Patriot missile interceptors - and possibly THAAD components -have reportedly been redeployed from South Korea to the Middle East. These are systems that have been central to deterring North Korean ballistic missiles. Their removal from the Korean Peninsula has raised quiet alarm among security analysts, with concern that Pyongyang may read the situation as an opportunity.
A Marine Expeditionary Unit has also been redeployed from Okinawa in Japan, a move that further reduces America's military posture in the Pacific.

A Sentiment Shift With Consequences

The ISEAS survey found that "US leadership under President Trump" is now the single biggest geopolitical concern among regional respondents, cited by 51.9 per cent. That exceeds concerns over China's behaviour in the South China Sea, which ranked second at 48.2 per cent.

The Philippines, heavily reliant on US security guarantees in its territorial disputes with China, has seen the share of respondents expecting worsening ties with Washington jump from 8.3 per cent to 21.8 per cent in a single year. Indonesia's figure rose from 19.1 per cent to 35.2 per cent.

Mr Ng Chee Khern, Director and CEO of ISEAS, put it this way : “This year’s survey underscores the growing complexity of Southeast Asia’s strategic environment. The findings show a region that is navigating external pressures, internal constraints and shifting global dynamics with increasing caution. At the same time, they reaffirm the continuing importance of ASEAN as a platform for stability, dialogue and regional cooperation.

New Zealand meanwhile has its own issues concerning fuel prices, possible shortages, rationing, and how to control the inevitable inflation in the local economy.

But while New Zealand is safely away from the blast zone, it now sits amid a region where the long-running faith in the architecture of security appears to be being questioned.

That faith has underpinned stability for the past 80 years, but if US credibility continues to erode and China positions itself as the stable alternative,the strategic landscape that New Zealand navigates could look very different within a decade.

-Asia Media Centre