History Shows Great Powers Collapse Without Robust Immigration
By Tom Kagy | 14 Dec, 2025

The United States is being led toward the decline suffered by Imperial Rome, Spain, China, Russia and today's Britain and Japan.

Sadly the United States is now saddled with a leader who played hooky during history class.   His crusade to choke off immigration and even deport migrants who have already established themselves as productive workers puts the US on precisely the path of the fallen great empires of yore, and today's declining middle powers.

The crucial lesson that Donald Trump and his supporters never learned is that no nation stays great without a steady inflow of new people.  Migrants replenish labor forces, expand the tax base, diversify skills, energize innovation, and offset the demographic gravity that pulls aging societies toward decline.  Throughout history rising powers forget this.  Confident in their cultural superiority or fearful of outsiders, they attempt to close themselves off just when they most need new lifeblood.  Again and again, the results follow a familiar pattern—slowing growth, diminishing influence, and eventual displacement by more open, more dynamic societies.

Today the United States is at a dangerous crossroads.  Despite having been built on successive waves of immigration and having drawn its greatest strength from the energies of newcomers, the ambitions of florid demagogue is moving it to restrict migration even as its population ages and its birth rate sinks to historic lows.  The debate is cast in cultural and political terms, but its economic and geopolitical implications are profound.  If history is a guide, shutting the gates will destroy America’s long-term prosperity and status as the number one superpower.

The greatest historical parallel is the Roman Empire.  During its ascent Rome absorbed conquered peoples, offered citizenship broadly, and allowed constant inflows of laborers, artisans, traders, and soldiers from across its expanding territories.  Roman identity was porous by design.  The empire grew by turning outsiders into insiders—creating a vast reservoir of manpower and talent.  In its later centuries, when Rome began tightening its definitions of citizenship and grew increasingly fearful of “barbarian” migration, its progress stopped and retreated.  Populations stagnated in core regions, the taxable base shrank, and the military could no longer be fully staffed by loyal Roman-born recruits.  The very groups Rome tried to exclude became the ones that eventually brought about its fall.

Imperial China offers similar lessons.   During prosperous periods—the Tang dynasty being the prime example—China was open to traders, scholars, and foreign communities.  Chang’an, the Tang capital, was one of the most cosmopolitan cities in the world, drawing Persians, Arabs, Turks, Indians, and Central Asians who contributed to trade networks, administrative talent, and cultural innovation.  Later dynasties, especially in their declining phases, turned inward, restricting movement and foreign influence.  Economic dynamism faded, military vulnerabilities grew, and political sclerosis deepened. The Ming dynasty’s abrupt cancellation of Zheng He’s ambitious maritime expeditions symbolized the dangers of withdrawing from global flows of people and ideas.  China’s long centuries of decline were marked by strict immigration controls, MAGA-like ethnic policies, and suspicion of outsiders.

The story repeats over and over around the world.   The Ottoman Empire flourished when it welcomed Jewish refugees fleeing the Spanish Inquisition and incorporated diverse groups into its economy and bureaucracy. These migrants brought commercial networks, administrative skills, and financial knowledge that strengthened Ottoman institutions.  As the empire aged, its ethnic nationalism and restrictive policies narrowed the definition of belonging.  Economic vigor waned as minorities lost protection or fled, and the empire fractured under the weight of internal divisions it once managed through inclusion.

Even Britain—the archetype of a global empire sustained by its vast network of territories—relied critically on migrants. The Industrial Revolution was driven not only by the inventions of native-born Britons but also by the contributions of Huguenot refugees, Irish laborers, Jewish entrepreneurs, and, later, Commonwealth citizens who filled essential roles in rebuilding post-war Britain.  Declining birth rates in the late nineteenth century were offset by migration from within the empire, enabling Britain to project influence for far longer than its industrial competitors might have expected.  In the postwar era, Britain’s recovery and modernization depended heavily on immigrants from India, Pakistan, the Caribbean, and Africa.  Later political movements like Brexit sought to restrict immigration sharply.  Today it suffers from cchronic labor shortages, stagnating productivity, and a shrinking global profile.

Modern examples reinforce the connection between demographic openness and sustained power.  Japan’s unparalleled rise after World War II eventually collided with a self-imposed demographic wall.  Its strict immigration policies, rooted in concerns about cultural homogeneity, became a structural constraint on growth.  Despite leading the world in robotics and engineering, Japan has been unable to overcome the economic drag of a rapidly aging population.  By the 2000s, it faced deflation, shrinking markets, and reduced geopolitical weight. I ts challenges went beyond economic mismanagement.  It has the racist tunnel vision shared by MAGA—a belief that a great nation can thrive or revive without new people.

Russia is another stark modern example of the decline caused by a lack of a robust labor force.   Its vast geography hosts a population shrinking rapidly from low birth rates, high mortality, and limited immigration.  Despite possessing abundant natural resources and nuclear capabilities, Russia’s long-term influence is constrained by the simple reality that it lacks enough people—especially young, skilled workers—to power sustained economic growth.  In recent years, emigration has compounded the problem, with educated Russians leaving for more open and prosperous societies. It is hard to maintain great-power status when your educated youth are voting with their feet.

By contrast some countries have thrived in the twenty-first century—the ones that embraced migration while managing it effectively.  Canada, once overshadowed by its larger southern neighbor, has become a model of migrant-driven growth.  Its points-based immigration system attracts high-performing workers, entrepreneurs, and students who integrate rapidly and help offset the country’s aging population.  Australia, too, has leveraged migration to fuel decades of economic expansion, rising wages, and robust innovation ecosystems.

The United States is the best example of the role migration plays in a nation's rise and decline.  America’s greatest periods of growth were inseparable from immigrant inflows—the Irish and Germans in the 19th century, Eastern and Southern Europeans in the early 20th century, and Asians, Africans, and Latin Americans in the post-1965 era.  Each wave replenished the country’s labor force, spurred industrialization, fueled technological leaps, and enriched American culture.  The United States became a global magnet for talent, drawing scientists, engineers, artists, entrepreneurs, and workers who shaped everything from Silicon Valley to the Manhattan skyline.

Immigrants have founded more than half of America’s most valuable startups and contribute disproportionately to patents, scientific breakthroughs, and new business formation. Higher education and research institutions depend on foreign-born graduate students and researchers. The US population would have been shrinking for the past two decades without immigration, with profound implications for Social Security, defense recruitment, infrastructure needs, and economic dynamism.

Yet politically, the discourse has shifted in the opposite direction.  Instead of channeling migration into strategic advantage, the United States increasingly treats it as a threat.  Both major political parties have proposed or enacted measures that restrict inflows, despite widespread labor shortages, declining fertility, and insufficient native-born population growth to sustain entitlement programs.  Semi-educated MAGA mouthpieces like JD Vance talks of replacing migrant workers with robotics and automation—a pipe dream for at least the next two decades or longer.  That's enough time for the labor and productivity deficit to bring about a Great-Depression-level collapse of the US economy, followed by rapid descent into a stagnant middle power like Japan.  

A great power stays great on perpetual renewal, not on seeking to restore some past age which too depended on a massive influx of immigrants to turn its vast lands and natural resources into the world's most efficient economic engine.  That engine needs renewal with new workers, new families, new entrepreneurs, and new communities that revitalize the national labor force and brainpower.  Demographically stagnant nations grow brittle, their industries lose edge, their fiscal burdens climb, and their influence ebbs—as history has abundantly demonstrated.

The United States stands at a moment of demographic reckoning.  Its median age continues to rise.  Retirements outpace new workforce entrants. Infrastructure, defense, and innovation require more skilled and unskilled workers than the native-born population can supply.  Meanwhile, dynamic young populations elsewhere in the world are seeking opportunities that the US has begun turning away.

History is unequivocal.  Openness to migrants isn't merely a humanitarian preference or a cultural choice.  It's a hard-and-fast strategic requirement for any nation that hopes to maintain great-power status across generations.  Nations that welcome newcomers with confidence and foresight tend to grow stronger, more resilient, and more innovative.  Those that close themselves off inevitably decline.

Sadly the United States is now being led by demagoguery away from a future of strength, prosperity, and continuing global leadership powered by an influx of talent and energy.  It has now turned away from the path that led to its greatness.