When America leaves, the Middle East redraws the rules

The quiet earthquake in Washington in January 2026 will not stay confined to American domestic politics. When the United States withdrew from dozens of international organisations tied to the United Nations, climate governance, global health and development, it sent tremors across every region that depends on rules rather than raw power. Nowhere will those tremors be felt more acutely than in the Middle East — and, by extension, across the Asia-Pacific.

For decades, the Middle East sat at the centre of the US-built multilateral system. UN peacekeeping missions, humanitarian agencies, climate funds and diplomatic forums formed the scaffolding that prevented regional crises from cascading into global disorder. That scaffolding is now visibly weakening. The United States was the largest single contributor to the World Health Organisation, providing roughly 18 per cent of its core budget in 2024. It was a central pillar of UN climate negotiations, a major funder of UNRWA, and a decisive voice in peace and security debates. The sudden retreat has created not just a funding gap, but a strategic vacuum.

The Middle East understands vacuums better than most regions. When global engagement falters, local power fills the space — often violently. Iran’s expanding network of non-state allies, stretching from Lebanon to Yemen, has proven resilient even under sustained military pressure. It’s been noted that despite heavy losses in 2024, the so-called ‘Axis of Resistance‘ has adapted rather than collapsed, embedding itself in political economies and state institutions. In the absence of strong multilateral constraints, such networks gai room to manoeuvre, shaping regional order on their own terms.

At the same time, Gulf states are recalibrating. Saudi Arabia’s costly intervention in Yemen left more than 21 million people dependent on humanitarian aid, a reminder that unilateral or coalition-based force cannot substitute for durable diplomacy. Riyadh’s subsequent détente with Tehran and deepening engagement with China reflect a sober assessment: US guarantees can no longer be assumed to be permanent. For Asia-Pacific economies reliant on Gulf energy flows and Red Sea shipping lanes, this strategic hedging matters. Houthis targeting commercial vessels in solidarity with Gaza have already added billions of dollars to global trade costs, with Asian markets absorbing much of the shock.

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The deeper issue, however, is not logistics. It is legitimacy. In July 2024, the International Court of Justice declared Israel’s occupation of Palestinian territories illegal under international law. That ruling resonated far beyond the Middle East. It spoke to the credibility of international law itself — the same legal architecture that underpins maritime rights in the South China Sea and arms control regimes across East Asia. When the world’s most powerful state steps back from the institutions that uphold those rules, the signal is unmistakable: law is optional, power is decisive.

For the Asia-Pacific, this is a dangerous precedent. Middle powers have long relied on multilateralism to amplify their voice and constrain coercion. Australia, Japan, Indonesia and South Korea have all benefited from a system where disputes are channelled through institutions rather than resolved through force. A Middle East drifting further into unmanaged rivalry erodes confidence in that system everywhere. The lesson drawn in Beijing, Moscow or Pyongyang will not be subtle.

The human cost is already visible. Gaza’s devastation, Yemen’s protracted humanitarian catastrophe, Syria’s frozen conflict and Lebanon’s economic collapse all intersect with the weakening of international engagement. UN agencies are being forced to cut programs just as needs reach historic highs. The UN estimates that more than 110 million people globally are displaced, with the Middle East accounting for a disproportionate share. These are not abstract numbers. Displacement drives instability across regions, including Southeast Asia, through irregular migration, labour shocks and security spillovers.

There is also a strategic irony at play. The United States justified its withdrawals on sovereignty grounds, yet pandemics, climate change and energy insecurity respect no borders. The US exit from the UN climate framework hands greater agenda-setting power to China at precisely the moment when the Indo-Pacific is grappling with climate-driven insecurity. Rising sea levels in the Pacific Islands, droughts across the Middle East and food price volatility in South Asia are part of the same systemic crisis. Fragmented governance makes all of them harder to manage.

History offers uncomfortable parallels. America’s refusal to join the League of Nations after World War I weakened collective security and preceded a period of global instability that ultimately dragged the US back into conflict at far greater cost. The Middle East, then under colonial mandates, became one of the theatres where that instability took root. Today’s retreat risks repeating the pattern in a far more interconnected world. 

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Yet the story is not solely one of decline. Vacuums can also provoke adaptation. European states are discussing greater strategic autonomy. Gulf countries are diversifying partnerships. Middle powers in the Asia-Pacific are quietly strengthening minilateral arrangements, from the Quad to ASEAN-led forums. Australia, with its deep investment in both Middle Eastern stability and Indo-Pacific order, has an opportunity to act as a bridge; supporting humanitarian relief, climate finance and diplomatic initiatives that reinforce, rather than replace global institutions.

The Middle East’s future will not be decided in Washington alone. But the erosion of multilateral leadership narrows the space for peaceful outcomes. Conflicts rooted in inequality, occupation and governance failure do not dissipate when international attention fades; they metastasise. Extremist narratives thrive on perceived abandonment. Revisionist powers thrive on disorder.

For the Asia-Pacific, the Middle East is no longer a distant arena of tragic but contained crises. It is a proving ground for the rules-based order itself. Energy security, maritime trade, climate resilience and the authority of international law converge there with unsettling intensity. The retreat of the United States from multilateralism accelerates that convergence.

The question facing regional and global actors is stark. Either collective institutions are reinforced — imperfect, frustrating, but indispensable — or the world drifts towards a system where influence flows from coercion and alignment shifts with every crisis. For middle powers whose prosperity rests on predictability, the choice should be clear.

The Middle East has taught the international system many lessons, often at immense human cost. One of them endures: when diplomacy recedes, violence advances. The Asia-Pacific, watching closely, has a profound stake in ensuring that this lesson is not learned yet again.

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The views expressed in this article belong to the author and do not necessarily reflect the editorial policy of Middle East Monitor.