The world has spent the past 80 years building the current multilateral system —anchored by institutions like the United Nations and the World Bank. Born from the devastation of two world wars, this system was largely designed and driven by the United States with the goal of ensuring lasting peace and shared prosperity.

Yet it took only a few months — perhaps a few years, if counting his first term — for President Donald Trump to seriously disrupt this structure. By withdrawing from or weakening key multilateral treaties and organizations, Trump fundamentally challenged the foundations of the international order.

The pressing question now is whether the multilateral world that has shaped global norms for eight decades can endure without the active engagement of the United States. Equally important: What role, if any, can middle-power countries like South Korea play in this evolving global landscape?

This is not a theoretical concern for Korea, which faces a pivotal presidential election in less than a month. As the international order shifts rapidly under the weight of Trump’s impulsive and unpredictable trade and security policies, Seoul must define and assert its role to stay relevant. In a new multipolar system where powers like the European Union and China are already moving to fill the vacuum left by US retreat, Korea needs leadership that understands and champions the multilateralism that has underpinned its economic and security gains for decades.

So what will the world look like in an era of American isolationism? Will the multilateral system collapse with the withdrawal of its chief architect? Unlikely. Institutions like intergovernmental organizations and other frameworks of global governance have weathered previous crises — such as oil shocks and regional conflicts — and have proven resilient. They may survive the current turbulence, but the contours of the system will inevitably shift. New norms and agendas will emerge, shaped by rising powers such as the EU and the BRICS countries — Brazil, Russia, India, China and South Africa, among others — who are increasingly asserting themselves on the global stage.

Since his second inauguration, Trump has pulled the US out of several intergovernmental organizations, including UNESCO, the UN Human Rights Council and the World Health Organization. He cited alleged anti-Israel and pro-China biases as justifications. These withdrawals, coupled with the US exit from the Paris Agreement on climate change, have seriously weakened multilateral institutions — especially given America’s historic role as a major funder and influencer. The WHO, for instance, has already reported funding shortfalls that it warns could endanger global health efforts.

Perhaps even more damaging is Trump’s aggressive trade policy. From day one of his second term, he imposed or threatened steep tariffs on both allies and rivals. Product-specific tariffs — on steel, automobiles and more — were layered on top. Trump’s latest move, a proposal for sweeping “reciprocal tariffs,” would impose a 25 percent blanket tariff on Korean exports to the US. His agenda is clear: Dismantle the WTO’s multilateral trade framework and replace it with bilateral deals where American leverage is maximized.

Despite this, multilateralism is likely to persist — though in a different form. Rather than being dominated by a single superpower, IGOs and other international mechanisms will be increasingly influenced by multiple major players. The EU, emboldened by Trump’s provocations, is already stepping up, not just in Europe but globally. European nations have committed to increased defense spending in response to Trump’s demands to restructure NATO. Similarly, regional organizations like the African Union and the Association of Southeast Asian Nations are poised to take on more active roles.

Non-Western powers, especially BRICS nations, will bring new momentum to multilateralism. China, India and others are already filling the leadership void with bold initiatives. China’s Belt and Road Initiative and the Asian Infrastructure Investment Bank directly challenge the US-dominated global financial architecture led by the World Bank and the IMF. Under such developments, even the supremacy of the US dollar could come under question, despite Trump’s rhetorical threats to uphold it.

This evolving multilateralism brings real risks. Chief among them is the infusion of values that challenge the West’s liberal, rules-based order. Disillusioned developing countries, alienated by Trump’s "America First" rhetoric, may be drawn to alternative systems that emphasize state sovereignty over democracy and human rights. A multilateral order led by authoritarian regimes, many of which now populate the expanded BRICS bloc, could prioritize control and coercion over cooperation and fairness.

That is precisely why middle powers like South Korea must step forward. Rather than remain a passive bystander, Korea should assert its voice to defend and promote a liberal international order from which it has greatly benefited. The UN military support during the Korean War and postwar financial aid from institutions like the World Bank were foundational to Korea’s security and economic rise. It is now Korea’s turn to help sustain the system in the absence — whether temporary or permanent — of its original architect.

This is no small task for a country of Korea’s size. But if it is serious about fulfilling its aspiration to become a “Global Pivotal State,” it must take the lead in key areas like digital governance, climate resilience and global health. Korea should proactively set the agenda and help shape international discourse, following in the footsteps of model middle powers such as Canada or Norway. And to share the burden, it must partner with other like-minded nations committed to multilateral cooperation.

Most critically, Korea must elect a leader who not only understands the value of multilateralism but is also willing to defend it at any cost. In an era of uncertainty and shifting power, that choice may determine not only Korea’s future, but also the resilience of the world’s rules-based order.

Lee Byung-jong

Lee Byung-jong is a former Seoul correspondent for Newsweek, The Associated Press and Bloomberg News. He is a professor at the School of Global Service at Sookmyung Women’s University in Seoul. The views expressed here are the writer’s own. -- Ed.