“International politics, like all politics, is a struggle for power.”
Hans Morgenthau wrote this foundational sentence from his desk in Chicago at the dawn of the Cold War, just as the United States and the Soviet Union embarked on an open-ended competition for global dominance. The volume that Morgenthau ultimately produced, Politics Among Nations, quickly became the most widely adopted international relations textbook in the United States. It provided an intellectual framework—known as realism—that would guide generations of scholars, diplomats, and policymakers through decades of geopolitical turbulence.
Although nearly eight decades have passed since Morgenthau’s most influential work was published, the fundamental dynamics of the global stage remain largely unchanged. Human nature, which for Morgenthau drove the relentless struggle for power, is unmoved by the passage of time. Sovereign states remain the most significant actors in the international system, continuously competing for influence, security, and advantage. Great powers continue to drive the broad course of history. Much of today’s complex geopolitical landscape seems to affirm Morgenthau’s stark conclusions: Russia’s aggressive attempts to establish a dominant sphere of influence in Eastern Europe, China’s persistent quest for regional hegemony in East Asia, and the United States’ revival of the Monroe Doctrine in the Western Hemisphere all point to the enduring primacy of national interests over abstract moral aspirations and international norms.
For many observers, Morgenthau’s contributions begin and end with his clear identification of power as the absolute key determinant of state behavior. But this reading misses one of his most vital core observations: that even if humans tend to be power-maximizing creatures, they are also moral beings who actively seek to limit their own power. Morgenthau’s extensive writings reveal a deep and continuous dialectic between power and morality—two seemingly incompatible concepts that he spent his entire life attempting to reconcile. Far from romanticizing power, Morgenthau saw an urgent, inescapable need to tame it.
As an immigrant who escaped Nazi Germany and owed his very life to the United States, Morgenthau had specific, hard-earned guidance to offer his fellow Americans. Even as he urged the United States to protect its vital national interests by maintaining a favorable balance of power in key geopolitical regions, he implored the country to wield its immense strength prudently. Morgenthau viewed the United States as the only nation with both the capacity and the moral will to fight on behalf of transcendent values that he believed power had to serve. He was deeply committed to preserving American power as a crucial check on the violence and bigotry he had personally experienced in Europe. Yet, he profoundly feared that U.S. overreach would hollow out the very foundations of that power, which he considered a tragedy for all of humanity.
Today, perhaps no government has misread Morgenthau more fundamentally than the second Trump administration. Its officials openly revel in the unconstrained exercise of military force around the world, ranging from operations directed against Iran to actions in Venezuela and the Caribbean, while frequently dismissing concerns regarding alleged war crimes and issuing direct threats to long-standing traditional allies. White House Deputy Chief of Staff Stephen Miller typified this outlook when he invoked the “iron laws of the world,” describing a global environment “governed by strength,” “governed by force,” and “governed by power.”
Some analysts have also erroneously rooted the Trump administration’s actions in classical realism. A lengthy essay in The New York Times Magazine, for instance, ran under the headline “The Theory That Gives Trump a Blank Check for Aggression.” This misinterpretation is understandable to a degree, as the Trump administration has repeatedly claimed that its aggressive foreign policy actions are underpinned by what it terms “flexible realism.”
However, any reading of realism that fails to consider the vital moral dimensions of Morgenthau’s theory is both profoundly mistaken and inherently dangerous. When the United States limits its own power by faithfully abiding by international norms, closely consulting allies and partners, and wielding its strength in the pursuit of transcendent values, other countries find American influence much more palatable, which in turn helps sustain it over the long term. But if Washington’s actions become entirely untethered from these essential restraints, other nations will no longer defer to American prerogatives, and the world will inevitably become a much more dangerous place.
Returning to the true foundations of realism—to the man who introduced this intellectual tradition to Americans—is critical. If Morgenthau were to witness this specific moment in U.S. history, he would likely conclude that the country had overlearned his lessons regarding the sheer importance of power and erred gravely in equating power with the unrestrained use of military force. He would see an urgent need to elevate moral questions and rebuild the normative constraints governing the exercise of state power. Furthermore, he would warn against foreign entanglements that actively undermine American democracy, which he always viewed as the fundamental wellspring of the country’s true power. These are the lessons that must help the United States navigate an era of intensified great-power competition, where the margin for error is exceedingly thin and the cost of miscalculation could be catastrophic.
Out of Europe
Morgenthau was born into an assimilated, middle-class Jewish family in southern Germany in the winter of 1904. His conservative and authoritarian father, Ludwig, raised his only child to revere the monarchy and take profound pride in their country’s cultural and scientific achievements. Morgenthau’s childhood might have otherwise passed as that of a shy, precocious boy growing up in a self-assured bourgeois community, but Germany’s devastating defeat in World War I and the subsequent, rapid rise of violent anti-Semitism set his life on a drastically different and perilous course.
In 1922, as a top-performing student in his high school, Morgenthau was chosen to address his classmates and local neighbors in a public ceremony honoring the school’s namesake. When he began to speak, he noticed with dismay that some attendees had turned their backs to him, while others openly held their noses in contempt at what they viewed as a “stinking Jew.” Morgenthau managed to finish his prepared remarks, but as he left the town square, his fellow classmates hurled vile anti-Semitic insults and spat upon him. Just months later, Adolf Hitler descended on Morgenthau’s hometown of Coburg with hundreds of stormtroopers, who violently assaulted protesters while local police looked on approvingly. Coburg soon gained the ignominious distinction of being the first German town to elect the Nazi party to formal power.
Morgenthau left Coburg hoping to pursue a career as a writer or poet, but he was forced to pivot to the study of law after hyperinflation completely ruined his family’s personal finances. During his apprenticeship under Hugo Sinzheimer, a leading left-wing labor lawyer, he witnessed conservative judges systematically undermine the Weimar Republic and actively aid those who sought its total destruction. Morgenthau later reflected in his intellectual autobiography that this formative experience led him to the inescapable conclusion that “what was decisive was not the merits of different legal interpretations but the distribution of political power.”
As life for German Jews deteriorated rapidly, he fled to Geneva to teach law. Switzerland was unfortunately not far enough away; after Hitler formally took power in Germany, university students began boycotting his classes because they refused to learn German law from a Jewish scholar. He subsequently found an academic position in Madrid, but was quickly displaced by the outbreak of the Spanish Civil War. He wandered through various European countries before finally arriving in New York in 1937 as a penniless refugee. Having witnessed the terrifying rise of fascism up close, Morgenthau was deeply shocked to find that so many Americans firmly believed human nature was fundamentally good, that peace was the normal and permanent condition of humanity, and that history was an unbroken story of inevitable human progress.
Settling first in New York and later in Kansas City, Morgenthau grew increasingly alarmed as the United States watched passively while Nazi Germany rearmed, annexed Austria, and systematically invaded Czechoslovakia. He firmly believed that a fundamental failure to understand the darker aspects of human nature had inspired Western democracies to place a blind faith in international law and the League of Nations, leading them down the path of least resistance through the disastrous appeasement of Hitler and straight into a moral abyss.
Shaken profoundly by the fall of France in 1940, Morgenthau began writing his very first English-language book, directly taking aim at Americans’ supreme confidence that the empirical methods of the natural sciences could adequately make sense of the complex social world, and that the sheer force of human reason would eventually eliminate conflict. In Scientific Man vs. Power Politics, published in 1946, he charged that contemporary rationalism and liberalism had fundamentally misunderstood the true nature of man, the nature of the world, and the nature of reason itself. Humans, in addition to possessing rational needs, also harbored deep irrational impulses that could never simply be reasoned away. Man’s “lust for power would be satisfied only … if he became like God.” Countries, operating much like individual humans, constantly sought to maximize their power over one another, thereby making international conflict structurally inevitable.
Scientific Man received universally disastrous reviews upon publication, and Morgenthau later recalled that it “shocked people to no end.” Recognizing the backlash, he adjusted his intellectual approach, carefully tailoring his message to American sensibilities and packaging it within a textbook format that would appeal directly to their practical nature. He wanted this subsequent book to mark a profound evolution in American thinking about foreign policy, privately writing that it would differ from its academic predecessors “as an automobile differs from a horse and buggy.”
Two years later, in 1948, with the publication of Politics Among Nations, he achieved that ambitious goal. Morgenthau stressed repeatedly that the struggle for power was utterly inescapable. All states invariably sought to keep, increase, or demonstrate their strength. Disarmament agreements, collective security pacts, and international law would never be sufficient to contain this deep-seated struggle. Only a functioning balance of power could prevent ambitious countries from attempting to violently overthrow the existing international order. Power, he argued, could only ever be successfully tamed by countervailing power.
Barbarism and Civilization
It is easy to understand why many casual readers misread Morgenthau as a simple champion of realpolitik—an intellectual heir to figures like Niccolò Machiavelli or Otto von Bismarck. After all, he unquestionably placed power at the absolute center of his analytical framework. However, he never romanticized it. As he clarified in a private letter: “I am an analyst of the nation state and of power and have emphasized time and again their negative moral connotations.”
Morgenthau’s personal, harrowing encounters with state power had taught him unequivocally that its unbridled, unchecked pursuit led directly to human calamity. He understood clearly that normative and moral limitations were desperately required to keep the inherent struggle for power within tolerable, civilized bounds. As he wrote in another piece of correspondence: “It is the task of civilized societies to temper the power drives and direct them into socially useful channels.”
Indeed, Morgenthau actually had far less intellectual tolerance for those who failed to reconcile power with morality than he did for those who merely underestimated power’s fundamental importance. Although President Woodrow Wilson’s sweeping universalism and naive idealism made him one of Morgenthau’s most frequent analytical targets, Morgenthau still preferred him to a cynical Machiavellian prince, writing: “Wilson’s failure was at least the failure of greatness, of too great a vision. Nobody will say as much for the epigones of Machiavelli.”
He similarly criticized the prominent British historian and political theorist E.H. Carr, whose profound moral relativism had led him to advocate for the disastrous appeasement of Nazi Germany. Carr, Morgenthau wrote, had “no transcendent point of view from which to survey the political scene and to appraise the phenomenon of power.” While both men are historically viewed as pivotal realist thinkers, Morgenthau witheringly concluded of Carr that “it is a dangerous thing to be a Machiavelli. It is a disastrous thing to be a Machiavelli without virtù”—meaning that it is completely ruinous to practice power politics devoid of genuine skill, ethical judgment, and restraint.
In Politics Among Nations, Morgenthau took strong issue with political leaders who both glorify the relentless struggle for power and actively reject any self-imposed limits on their own use of force. He argued convincingly that “philosophies and political systems which have made the lust and the struggle for power their mainstay have proved impotent and self-destructive.” Furthermore, he drew crucial attention to the common moral standards that could successfully sustain international order and moderate the bitter struggle for power. He observed that throughout recorded history, humans have consistently insisted on subjecting political actions to rigorous ethical scrutiny.
When such normative restraints held firm, countries routinely did far less than their sheer physical power enabled them to do. Once-commonplace practices—such as assassinating a rival country’s political leaders or deliberately killing large portions of a civilian population simply to reduce an adversary’s military strength—became heavily stigmatized by the international community. Morgenthau concluded: “What has changed is the influence of civilization which makes what is desirable and feasible ethically reprehensible and, hence, normally impossible of execution.”
In the immediate, devastating aftermath of World War II, however, he firmly believed that the traditional limitations constraining the struggle for power had reached their weakest point since the advent of the modern state system. Hitler had attempted the total industrial extermination of an entire people, and both the Axis powers and the Allied forces had bombed civilian population centers indiscriminately. Although Morgenthau firmly believed that the Western Allies were morally justified in taking such extreme actions to defeat an absolute, genocidal regime, he nonetheless deeply feared that the overarching struggle for power was well on its way to becoming entirely boundless. In the dawning nuclear age, failing to reestablish these essential moral barriers could very well mean the literal end of human civilization.
The Good Fight
Morgenthau’s hard-nosed reputation has long obscured the deeply moral core of his realism. He was entirely unequivocal that power must always be treated as a mere means to an ultimate end—“an attempt to realize moral values through the medium of politics.” He recognized fully that maximizing power for its own sake was both mutually destructive and utterly pointless, arguing that “a nation must pursue its interests for the sake of a transcendent purpose which gives meaning to the day-to-day operations of its foreign policy.” In his view, ancient Greece and Rome are enduringly remembered today not for their raw armies, but because their power served a higher purpose that outlived their physical empires: specifically, Athenian democracy and philosophy, and Roman law and republican government.
As he successfully assimilated, built a professional career, and raised a family in Chicago, Morgenthau came to view the United States as the true modern inheritor of this noble historical tradition. The country’s profound contribution to the world, and the true underlying source of its immense power, lay directly in its vibrant democracy and robust civic life. A realist approach—one that prudently and carefully wielded power abroad—was ultimately best suited to protect the domestic American experiment, enabling ordinary citizens to live in enduring freedom and security while offering a shining example for other countries to freely emulate.
In other words, American power had to be permanently bound to a higher purpose—a purpose the country fulfilled “as a light to attract strangers, not as a flame to be spread throughout the world.” This was not merely the abstract observation of a dispassionate academic scholar. The United States had generously accepted Morgenthau when virtually no other country would take him in, and it stood as a place where foreign-born immigrants like him could rise to the very top of their respective fields through merit.
By the 1960s, however, Morgenthau saw clearly that American power was facing a severe, unprecedented threat entirely of its own making. He began to develop deep, vocal misgivings about growing U.S. military intervention in Vietnam, warning as early as 1961 that the conflict risked becoming a bottomless quagmire directly reminiscent of France’s disastrous war in Algeria. Two years later, as violent clashes between the South Vietnamese government and local protesters intensified, Morgenthau urgently implored the United States to withdraw entirely.
He built his opposition strictly on realist grounds, arguing forcefully that a communist takeover of Vietnam would not fundamentally alter the vital balance of power in Asia. In doing so, he directly rejected the popular domino theory, which held that communism would spread inexorably outward across the region once it gained a single local foothold. Morgenthau also astoundingly recognized early on that global communism was no longer a monolithic block, believing that figures like Ho Chi Minh could potentially lead a nonaligned communist country much like Josip Broz Tito had successfully done in Yugoslavia. He viewed the unfolding conflict primarily as a complex civil war, and he deeply worried that the United States was foolishly attempting to prop up a corrupt status quo that was itself the primary source of regional instability.
Successive U.S. administrations stubbornly failed to heed Morgenthau’s prophetic warnings, choosing instead to plunge the country deeper and deeper into the Vietnam War. Growing increasingly frustrated, Morgenthau came to deeply resent American policymakers’ profound misappropriation of his core lessons on power, prompting him to enter the public political debate with renewed vigor. At a massive, packed anti-war rally in New York’s Madison Square Garden in June 1965, he warned publicly that a guerrilla war of that nature could only ever be won through the indiscriminate killing of the South Vietnamese people, which would permanently tear at the moral fabric of the United States. Later that month, Morgenthau famously debated President Lyndon B. Johnson’s national security adviser, McGeorge Bundy, on national television, leading resolutely with his moral outrage: “I am opposed to our present policy in Vietnam on moral, military, political, and general intellectual grounds.”
The single greatest risk of the war, Morgenthau discerned with absolute clarity, was “the risk to ourselves, to our mission in the world, to our very existence as a distinct nation.” He lamented passionately: “Here is the last best hope of the downtrodden and the enslaved, to which men of good will throughout the world have looked as a shining example, relieving its frustration in blind ideological fury and aimless destructiveness upon a helpless people.” Vietnam, in his powerful telling, had thoroughly corrupted the very national purpose that gave American power its true meaning and legitimacy.
Squandered Inheritance
The tragic outcome of the Vietnam War powerfully validated Morgenthau’s core belief that unbridled power untethered from questions of morality would inevitably lead to disastrous overreach. It proved conclusively that the United States had a profound national interest in self-constraint, if only to avoid catastrophic self-destruction. More fundamentally, the Vietnam experience demonstrated that reckless foreign misadventures could easily boomerang inward, severely weakening American democracy, fraying societal cohesion, and ultimately undermining the country’s standing across the globe.
The foreign policy record of the second Trump administration has thrown these enduring insights into sharp, alarming relief. Its officials view fundamental questions of morality as a costly, irrelevant sideshow—the naive remit of woolly-minded idealists who simply do not understand how the harsh world really works. The White House has resorted time and again to the unilateral use of military force, conducting aggressive strikes against boats in the Caribbean, orchestrating the abduction of Venezuelan President Nicolás Maduro, enforcing economic blockades against Cuba, and openly waging hostilities against Iran. Furthermore, the administration has repeatedly threatened aggressive military action against Canada and Denmark, two of the nation’s oldest and most steadfast long-standing allies.
American democracy, far from continuing to serve as “a light to attract strangers,” is fast becoming a cautionary tale for the rest of the world. The second Trump administration has systematically undermined the institutional foundations of American power through sustained political attacks on the independent judiciary, the free press, and higher education institutions. It has gleefully bulldozed through any and all constitutional checks on its executive writ. Its assault on domestic institutions and its aggressive foreign policy are deeply intertwined; the administration not only entirely failed to seek proper congressional authorization for its military actions regarding Iran, but it also refused to even make a good-faith case to the American people prior to launching strikes.
President Donald Trump has repeatedly justified his administration’s outward aggression on the basis of the supposed “iron laws that have always determined global power.” Morgenthau would never have recognized this crude formulation as genuine realism. He consistently contended that “superior power gives no right, either moral or legal, to do with that power all that it is physically capable of doing.” The Trump administration, by stark contrast, seems to operate under the dangerous assumption that to refrain from using the military power at its disposal is to waste it. Morgenthau’s devastating historical verdict on E.H. Carr applies with equal force to the current administration: they are functioning as “Machiavellians without virtù,” playing reckless power politics devoid of genuine judgment and leading their country toward avoidable disaster.
Morgenthau would argue persuasively that the Trump administration fundamentally misunderstands the very concept of power itself. Power should never be crudely equated with raw military might; rather, it must be understood as a complex, delicate psychological relationship built heavily on persuasion and mutual interests. Real power, Morgenthau insisted, always lies in the ability to influence another country through consent and cooperation, not through brute coercion. In this analytical view, the frequent, uninhibited use of military force actually signifies the profound abdication of true political power rather than its ultimate culmination. The Trump administration’s constant belligerence betrays its underlying weakness: its frantic acts of global aggression are silent confessions of its ultimate inability to shape international events through sophisticated diplomatic means.
Although Morgenthau grew up steeped in the traditional statecraft of Bismarck, he came to admire Abraham Lincoln above all other American statesmen, even attempting to write a major book about him toward the very end of his life. Morgenthau saw in Lincoln a rare, visionary leader who was never blindly possessed by power, but who instead masterfully possessed it and, ultimately, subordinated it completely to higher, transcendent values. Today, just as at the height of the tumultuous Vietnam War, Morgenthau would see his primary intellectual and civic task as restoring morality and ethics to their rightful place in statecraft, highlighting the absolute necessity for national power to move the world closer to genuine justice.
The United States has dangerously lost its overarching national purpose, and unless it actively rediscovers it, discrete, short-term foreign policy successes will remain entirely irrelevant. As Morgenthau wisely wrote, if the country ultimately loses its soul, any temporary victories achieved along the way are merely “footnotes to the history of the decline and fall of a once great nation.”
