When Xi Jinping, during his recent meeting with Donald Trump, emphasized that “Taiwan is China’s military red line” and warned that the two powers must not drift toward the “Thucydides Trap,” many interpreted these remarks merely as part of the escalating tensions between Washington and Beijing over East Asia. But the reality is that these positions are about far more than Taiwan alone; they reflect China’s new assessment of American power after the Iran war.
For Beijing, America’s war against Iran was not merely a Middle Eastern crisis. Rather, it was a test of Washington’s real capacity to manage the global order. The conclusion China’s leaders appear to have drawn from that test is hardly encouraging for the United States: contrary to its traditional image, America is no longer the focused, low-cost, invincible superpower of the post–Cold War decades. The Iran war revealed that Washington is now more entangled than ever in strategic overextension, resource attrition, and a crisis of geopolitical focus.
In this sense, Xi Jinping’s remarks regarding Taiwan should be understood not merely as a regional warning, but as a distinctly Chinese reading of the strategic consequences of Trump’s failed Middle East policies. By entering into military confrontation with Iran, the Trump administration sought to achieve several grand objectives simultaneously: restoring American deterrence, reasserting Washington’s authority in the Middle East, and sending a message of strength to global rivals, particularly China and Russia. In the logic of the White House, a display of force against Iran could prove that the United States still possessed the ability to dictate the rules of the global order.
But the problem was that the Iran war, contrary to initial expectations, did not become a short, low-cost operation. The energy crisis, threats to maritime routes, retaliatory attacks on American bases, rising military expenditures, and the necessity of maintaining an extensive regional presence gradually pulled Washington into the very same cycle of attrition it had previously experienced in Iraq and Afghanistan.
This war not only failed to revive American deterrence; it exposed the widening gap between the “image of power” and the “actual capacity of power.”
For China, this issue carried vital significance. For years, Beijing has been evaluating a central question: does the United States truly possess the ability to manage several major global crises simultaneously? From the perspective of Chinese leaders, the Iran war was the first serious indication that the answer to this question may be negative.
China has long concluded that America’s greatest weakness is “strategic overextension” — a condition in which a hegemonic power, in order to preserve its global position, becomes compelled to engage on multiple fronts simultaneously, gradually exhausting both its focus and its resources.
The Iran war intensified precisely this pattern. Today, Washington must simultaneously manage the Ukraine war, the Middle East crisis, and intensifying competition in the Indo-Pacific. This strategic dispersion not only drains America’s military resources, but also diminishes its decision-making capacity and geopolitical concentration.
Xi Jinping’s recent remarks on Taiwan therefore carry a meaning that extends far beyond East Asia. When China’s leader speaks explicitly of a “military red line,” that position is informed, at least in part, by the assessment that the United States after the Iran war is more vulnerable and more exhausted than it itself imagines.
In effect, Beijing now views America as a superpower excessively consumed by multiple crises — and precisely for that reason, one whose deterrent power has weakened.
One of the most important consequences of the Iran war was the erosion of the credibility of American deterrence. Deterrence depends not only on military power itself, but also on the perception that a great power possesses both the capability and the will to use that power effectively and sustainably.
Yet the Iran war produced a very different image: an America forced to bear ever-increasing costs merely to sustain its presence; an America whose public no longer has the tolerance for wars of attrition; and an America confronting severe domestic polarization and economic pressure at the very same time as external crises.
China is observing these signs carefully. Under such conditions, Xi Jinping’s warning about the “Thucydides Trap” acquires a new meaning as well. The concept does not merely refer to the danger of war between a dominant power and a rising one; it is also an implicit acknowledgment that the United States, in response to the erosion of its deterrence, may resort to more aggressive and risk-laden policies.
From Beijing’s perspective, the principal danger lies in the unpredictability of an America that senses its hegemonic position is eroding. Perhaps the greatest mistake of Trump’s foreign policy was that, at the very moment when the center of gravity of global power was shifting toward Asia, it once again entangled the United States in Middle Eastern crises.
The defining competition of the twenty-first century is not taking shape in the Persian Gulf, but in the Indo-Pacific. Yet Washington once again devoted a substantial share of its military resources, financial capacity, and political attention to a war that lacked any clear strategic achievement.
This was precisely what China wanted. For Beijing, the ideal scenario is not direct war with the United States. Rather, it is for Washington to remain trapped in costly and exhausting crises. The more American military capacity becomes tied down in the Persian Gulf, the more constrained its hand becomes in the Pacific; and the more financial and political resources are consumed in war with Iran, the less capable Washington becomes of containing China over the long term.
For this reason, Xi Jinping’s remarks on Taiwan must be understood within the broader context of the Iran war. Beijing’s growing self-confidence is, to a significant extent, the product of its perception that the United States is losing its strategic focus.
What is unfolding today in U.S.–China relations is not merely a traditional rivalry between two powers; it is a sign that the world is entering a phase of “hegemonic transition” — a phase in which the dominant power no longer possesses the ability to enforce the previous order, while the emerging power has not yet fully replaced it.
In such periods, the danger of miscalculation rises dramatically. If Washington continues to believe that it can manage multiple global fronts simultaneously through reliance on military power, it will likely not only fail to contain China, but also accelerate the erosion of American power itself. The Iran war may have been intended as a demonstration of the return of American authority, but in practice it became a stage upon which the real limitations of Washington’s power were laid bare.
Beijing has received that message. And perhaps most importantly of all, China’s leaders now believe that time is no longer working against them, but moving in their favor.
