For months, the United States has been locked in a grinding conflict with Iran, a war that shows no signs of resolution. President Donald Trump oscillates between threats of annihilation and offers of peace, but the underlying reality is unmistakable: American military power, once unchallenged, can no longer subdue even a mid-sized regional power like Iran. This is not merely a tactical setback; it is a symptom of a deeper, structural decline in US global hegemony.
To understand what is happening, it is useful to look back at another empire in its twilight. In 1942, as Britain faced its darkest hours in World War II, the editors of the London Times published a remarkable editorial. They foresaw that the British Empire, then still covering a quarter of the globe, was a “self-liquidating concern.” Its motto, “Imperium et Libertas,” had become a contradiction. Once the temporary advantages of naval dominance, industrial supremacy, and weak rivals faded, the empire’s reliance on coercion could not hold. Within five years, India was independent, and the empire began to unravel.
Fast forward to May 2026, and a similar diagnosis appears in the pages of the New York Times. Contributing editor Christopher Caldwell argues that America is now “officially an empire in decline.” He points to striking parallels: Britain was deindustrializing, overcommitted, and essentially bankrupt by 1945. It managed a relatively graceful decolonization, giving up territories it could no longer afford and ending on good terms with many former colonies. Trump, Caldwell suggests, had a chance to do something similar in his second term—withdrawing to a more limited sphere of influence, focusing on the Western Hemisphere. Instead, the intervention in Iran has dangerously overextended the empire, marking a watershed in its decline.
The Economic Foundations of Hegemony
The numbers tell a stark story. In 1945, the United States produced 50% of global economic output. Today, using Purchasing Power Parity (PPP), the IMF calculates that China produces 20%, the US just 15%, and the European Union 14%. This relative decline is not a failure of American capitalism; it is a testament to the success of the US-led global order in fostering growth elsewhere. The International Monetary Fund, the World Bank, and the World Trade Organization helped rebuild Europe, Japan, and later Asia. But that success has eroded the very dominance that made it possible.
For Asia, this shift is profound. The US security umbrella, which has guaranteed stability from Tokyo to Seoul to Manila, is no longer as credible. The war in Iran has stretched American resources thin, and as Washington's five miscalculations in Iran show, the costs are mounting. Meanwhile, China’s economic rise continues, and Beijing is increasingly assertive in its neighborhood. The question for capitals from New Delhi to Jakarta is whether the United States can still be relied upon as a guarantor of order.
Modern empires, as history shows, do not last long. Britain’s global empire spanned roughly 90 years (1857–1947), France’s African empire about the same, and the Soviet Union’s Eastern European bloc barely 40 years (1945–1989). The American imperium, dating from 1945, has already lasted 80 years—perhaps as long as any modern empire can reasonably expect. The acceleration of economic and technological change only shortens the lifespan of such systems.
The implications for the Indo-Pacific are direct. The US is now locked in a war with Iran that has no clear exit, while simultaneously trying to manage competition with China. As Trump and Xi manage their rivalry, the risk of miscalculation grows. In the North Pacific, deterrence remains a priority, but the resources to sustain it are finite. The American empire, like the British before it, is discovering that its means are no longer adequate to its ends.
This is not a cause for celebration in Beijing or elsewhere. The end of American primacy will not automatically lead to a more peaceful or prosperous world. It will, however, force every nation in Asia to recalibrate. The era of a single superpower is ending, and the multipolar order that replaces it will be more complex, more competitive, and more dangerous. The autopsy of the American empire is not just an academic exercise; it is a guide to the future we are already living.
