“America First” is no longer just a slogan—it’s the ideological cover for a new kind of abdication. Trump’s second term signals not a calculated retrenchment, but a performative and erratic rejection of global leadership. What replaces U.S. engagement isn’t multipolar order—but growing fragmentation, where authoritarian powers fill the vacuum and institutions lose their coherence. This isn’t realism. It’s disruption for its own sake—and the consequences will last far beyond this administration.
Soon after taking office, Trump formalized the U.S. withdrawal from the United Nations Human Rights Council, criticizing the body as biased and ineffective in protecting human rights. Trump signaled a possible reduction of the U.S. military footprint in Europe, warning that Washington would no longer shoulder the burden of European security without greater allied contributions — a move that deepened uncertainty among European leaders about the future of the transatlantic alliance.”
These decisions might seem disconnected. But they are part of a larger shift that demands a fresh lens—beyond the usual debate in International Relations theory between engagement and retrenchment. What we are witnessing now is not simply a U.S. pulling back to focus on domestic priorities. It is a vacating of the field, leaving allies exposed, adversaries emboldened, and the rules of the game up for grabs.
To put it bluntly: the United States is no longer leading—and the world is already adjusting.
In response to shifts in U.S. foreign policy under President Trump’s second term, nations worldwide are actively reassessing their security strategies. In Europe, French President Emmanuel Macron is advocating for substantial increases in defense spending among EU member states, proposing “massive, common funding” to unlock investments of hundreds of billions of euros for European defense and security. Germany is also making significant moves, with lawmakers approving an amendment to the constitution to implement the most extensive rearmament since World War II.
In the Indo-Pacific region, Japan is strengthening security cooperation with India and South Korea, aiming to create a multi-layered network of alliances to address growing security threats. Similarly, Australia and New Zealand are enhancing their military capacities and deepening bilateral and regional defense cooperation in response to a perceived retreat of U.S. influence and China’s increasing assertiveness.
And this is where the deeper danger lies. Trump may see his foreign policy as a return to realism, but it bears little resemblance to the strategic restraint theorized by figures like John Mearsheimer. Unlike traditional realists who argue for reducing exposure while preserving power, Trump’s approach is reactive, inconsistent, and performative. It confuses withdrawal with strength, and views alliances as burdens rather than multipliers of influence.
The vacuum left behind isn’t staying empty. As the United States recalibrates its global engagement, other nations are expanding their influence to fill the emerging void. China has significantly increased its presence in Africa, Latin America, and Southeast Asia through extensive infrastructure projects and strategic investments. In Southeast Asia, China has stepped in to fund aid projects, such as those in Cambodia, following the withdrawal of U.S. assistance, thereby strengthening its regional influence. On the multilateral front, global institutions like the G20 are experiencing challenges in achieving consensus, reflecting a trend toward fragmentation. For instance, the G20 finance ministers’ meeting in Cape Town failed to produce a joint communique due to disagreements over climate finance and trade policies, highlighting the difficulties in maintaining unified approaches to pressing global issues.
This isn’t just bad for the world—it’s bad for America. Trust, once lost, is hard to rebuild. Allies who hedge their bets today may not return tomorrow. When the U.S. treats its commitments as temporary and its partnerships as negotiable, it sends a message that will outlast any administration: America is not reliable.
Yes, retrenchment has its appeal. It promises fewer wars, leaner budgets, and more attention to domestic issues. And to Trump’s supporters, that promise is being fulfilled. But in an interconnected world, retreat does not equal safety. It equals uncertainty, and in many cases, danger.
The engagement versus retrenchment debate has long defined U.S. foreign policy—and scholars will continue to argue its merits. But Trump’s second term is different. This is not strategy. It is strategic abandonment. And its consequences are already unfolding.
The world is not just reacting to Trump’s foreign policy—it is evolving beyond the expectation of American leadership. In that evolution, a multipolar world is not emerging in an orderly fashion but through improvised adaptation to U.S. unpredictability. That, not withdrawal, is the most destabilizing legacy of Trump’s second term.
History may one day describe this era not just as a period of American absence, but as the moment when the world stopped waiting for the United States to return. In stepping back, America isn’t just changing its role—it may be surrendering it for good.
Dr. Nikolaos Lampas is Program Coordinator for IREA Program and Assistant Professor in International and European Affairs.
