Jürgen Habermas (1929–2026) dominated post-war European liberal philosophy. He dedicated his life to the rational foundation of a global liberal order and the post-national European Union.

　　Loaded with philosophical terms, his writing does not invite the reader, yet there is pathos in the background. Habermas addressed the question of whether the Enlightenment was the cause of the German genocides and Germany’s own ruin. Postmodern thinkers levelled this charge, but Habermas’s biography told against it: “Since the age of 16, my political thinking has been nourished by the American ideals of the late eighteenth century thanks to the shrewd re-education policy of the Allied occupation administration.”

　　To Habermas, modernity was synonymous with constitutional democracy based on human rights. He shaped the conventional wisdom of the post-war West that a secular, rationalist politics could silence “totalitarian political ragings.” Yet before his passing, his brand of human rights jurisprudence seemed dated. Though painstakingly elaborated in many large and impressive volumes, events like Kosovo, the Global War on Terror, and Gaza, gave the lie to his theories. Intellectually, he sparred with other prominent European contemporaries, like Michel Foucault, Carl Schmitt, and Pope Benedict XVI, and today it is their thinking about power, populism, and religion that appears to better match our political reality.

　　The Power of Speech

　　To exonerate the Enlightenment, Habermas pushed a common front between three sources of modernity: the American Revolution’s constitutional democracy, “the orienting power of the French Revolution” and rights, and Immanuel Kant’s rational freedom. 

　　Habermas never stopped working, completing a three-volume work on the history of ideas just last year. The trilogy argues that the Enlightenment decisively shifted Western populations from a cosmological to a postmetaphysical sense of life. Politics no longer defers to divine or natural hierarchies, argues Habermas, but rather draws only on the human wherewithal to frame constitutions worthy of rational dignity. Habermas celebrates the ideal of the constitutional state that “there is no ruling authority derived from something antecedent to the law” and “the egalitarian universalism, which is immanent in law and its procedures, has, as an empirical matter, perceptibly left its mark on the political and social reality of the West.”

　　Habermas earned his doctorate in 1954, and around that time, Schmitt’s ideas took off again amongst thinkers of both left and right.

　　Natural law has no role in contemporary order, contends Habermas. It is dependent upon an outdated cosmology. Instead, Habermas proposes the concept of communicative action. Affirming the West’s long-held faith in the power of speech—whether the orators of Athens, the biblical idea of God as the Word, or the coffeehouse debating societies of the 1700s—Habermas argued that positive law is sufficiently robust to bind communities. Taking up Aristotle’s proposition that “man alone of all animals possesses speech,” he argued that it is the nature of speech to make verifiable claims consistent with the social interaction they honestly address. “A reasoning public” can determine the legality of any state-enacted law—including “coercive state authority”—through normative speech that is falsifiable, coherent, and sincere. In signature Habermas-speak: “Communicatively generated legitimate power can have an effect on the political system insofar as it assumes responsibility for the pool of reasons from which administrative decisions must draw their rationalizations.”

　　If this strikes some as milquetoast, that is by design. With Germany’s ruin and Habermas’s “shrewd re-education,” he was grateful that “in our post-heroic age war is no longer a preferred mechanism for solving international conflicts.”

　　With the Global War on Terror, Habermas regrettably concluded that “the normative authority of the United States of America lies in ruins.” His most accessible book, The Divided West (2004), argues that the Bush administration’s response to 9/11 broke apart the West’s common front of post-heroic cosmopolitan law: “The Bush administration has laid the 220-year-old Kantian project of juridifying international relations ad acta with empty moralistic phrases.” In the 9/11 atmosphere of righteous indignation, the intimidating deployment of American power shredded Habermas’s certainty that the West had internalized democratic constitutionalism. For years, he had sincerely believed that “the decisionist substance of political power is more and more liquefied in the melting pot of the communication flows of organized transnational negotiations and discourses.” 

　　Power Old and New

　　Iraq was shattering because US action seemed to confirm the thesis of Foucault, that liberal institutions were mere camouflage for rank power. Foucault challenged the vision of the Enlightenment made famous in Kant’s essay, “What Is Enlightenment?” Kant argued that in past ages, peoples had been beholden to teachers, priests, and physicians, but in the new age of reason, “mature adulthood” would slough off these controls. The emerging human sciences of economics, anthropology, and sociology, he was sure, had given persons the wherewithal to understand the causes of social life and provide resources for free institutions. 

　　In seminal historical studies of madness, punishment, and sex, Foucault showed how the new sciences did not escape the old realities of power. Turning to Kant’s contemporary, Clausewitz, Foucault argued that science gave power a new target-set. Foucault discerned in the new sciences a biopolitics, an intensification of power insinuating itself into our bodies. An example is today’s massive wellness industry. Deploying a huge dataset, this knowledge industry shapes the institutional setting of the mental health counsellors at schools, firms, and professional sports franchises. It comprises the bloodwork for our annuals at the doctor’s office, our skin and hair routines, and even our yoga camps at destination resorts. Already huge, the dataset mushrooms as wearables relay information to companies and bureaucracies, who then refresh their wellness directives. Behind the patina of care, power stirs.

　　Habermas discounted Foucault’s biopolitics as aesthetic modernism: it pushes “into the sphere of the far-away and the archaic the spontaneous powers of imagination, self-experience and emotion. To instrumental reason [Foucauldians] juxtapose in Manichean fashion a principle only accessible through evocation, be it the will to power or sovereignty, Being or the Dionysiac force of the poetical.” Foucault was victim, thought Habermas, to “the shock of what is absolutely strange, cryptic, or uncanny.” America fell similarly victim after 9/11. In the offing, Habermas sensed the return of Schmitt’s heroic politics, where “the high ethos of justice is combined with the severity of decisionist power.”

　　Kosovo and Tehran

　　Even before the uncanny returned to the world stage at 9/11, older, more Thucydidean political realities were nipping at Habermas’s heels. Limits to “the Kantian project of constitutionalizing international law” had surfaced a couple of years earlier during the Kosovo War.

　　As part of NATO, the German Army fought in the Kosovo War of 1999. A watershed moment, it marked, commented Habermas, “the end of a long period of restraint which had imprinted itself on the civil traits of the postwar German mentality.” To his credit, Habermas did not dilute the dilemma of the Bundeswehr killing to save lives. The philosophical problem was that the Clinton administration had made the promotion of human rights “the national mission of a world power,” but “according to the premises of power politics.” Thus, the German Army’s participation in a war beyond Germany’s jurisdiction had no legal authority. By the strictures of positive law, for the intervention to be lawful, an international juridical order is necessary, yet none existed. Habermas was trapped. For moral reasons, he wanted the intervention in the national rights of Serbia. He was thus compelled to argue that “NATO’s self-authorization” of war for human rights was an “anticipation” of an aborning “institutionalization of cosmopolitan law.” 

　　Absent positive law, Habermas worried that NATO’s violent “struggle against evil” Serbia confirmed Schmitt’s theory that the abstract universalism of Enlightenment rights devolves into the worst kind of moralism backed by militarized cruelty. Schmitt (1888–1985) dominated legal circles in the run-up to World War II but after interrogation at Nuremberg, he was consigned to retirement. Habermas earned his doctorate in 1954, and around that time, Schmitt’s ideas took off again amongst thinkers of both left and right. Specifically, interest grew in his thesis that law is, as Habermas quotes him, “a compromise between justice and glorious splendour.”

　　Schmitt argues that the human being is “risky.” The only way to contain violence and build security is to craft legal boundaries along a friend-enemy faultline. The opposite of cosmopolitanism, the friend-enemy distinction, reports Habermas, legitimates “the self-assertion of the identity of a people or a movement.” Law, argues Schmitt, must moderate its ambitions and concede that peoples will go to great lengths to defend their ways of life. Schmitt’s populism not only scorns the idea of a post-national Europe, but he also proposes that Kant’s fulsome legalism subverts the rule of law and invites war.

　　Schmitt’s nationalism was a tough nut for Habermas to crack on account of its connection with religion, a topic around which, he confessed, he was “unmusical.” Wanting “a radically this-worldly politics,” Habermas worried about Schmitt’s political theology that, in his gloss, “through symbols, signs and ceremonies, through body language, gestures, clothing and rhetoric, the ruler provides testimony of his mystical participation in divine rule.”

　　Sure that “in a liberal democracy, state power has lost its religious aura” thanks to “bureaucratic depersonalization,” in 2004, he debated Cardinal Joseph Ratzinger, who became Pope Benedict XVI a year later. Both men had been conscripted into the Wehrmacht as child soldiers at the close of the war. 

　　Habermas had a sweeping knowledge of philosophy and law, yet held to an oddly narrow version of the Enlightenment.

　　Habermas opened the debate, conceding that “liberal societal structures are dependent on the solidarity of their citizens.” He also granted that Christian moral thought had indelibly marked legal theory, providing “normative conceptual clusters with a heavy weight of meaning, such as responsibility, autonomy, and justification.” Nonetheless, he insisted, the religious identities of peoples play no part in their roles as citizens, and religious speech must be translated into a language deferring to “the boundaries of the Enlightenment.” 

　　To circumvent this liberal defence, Ratzinger replied that the West has “two great cultures … the culture of the Christian faith and that of secular rationality.” He granted that “secular culture is largely dominated by the strict rationality of which Jürgen Habermas has given us an impressive picture.” Furthermore, Ratzinger acknowledged that natural law, reliant on cosmology, is unpersuasive. However, in its personalist variant, natural law retains its power, since human deliberation does not invent the “self-subsistent values that flow from the essence of what it is to be a man.” 

　　Going on the offensive, Ratzinger argued that “science can never show us more than partial aspects” of our existence and that history is replete with democratic votes for unjust laws. In addition, there are the “pathologies of reason” to consider. Utilitarian logic dropped the atom bomb. Similarly, eugenics and transhumanism both make use of “the breeding and selection of human beings … thought up by reason.”

　　The debate concluded with Habermas recounting a visit to Tehran in which it was pointed out to him that European secularization is an anomaly amongst world civilizations. Habermas told his interlocutor that this observation “reminds one of the mood in the Weimar Republic in Germany after the First World War—it evokes Carl Schmitt.” Picking up on the story, Ratzinger countered that “the question put by Jürgen Habermas’ colleague in Tehran seems to me not devoid of significance.” The argument that religions orient civilizations is compelling, and it is inappropriate to “reduce this question to the mood of Carl Schmitt.” Ratzinger concluded the debate arguing that restricting the West to the secular tradition “needs to be corrected” for without religious knowledge, reason will not stay innocent long.

　　Habermas had a sweeping knowledge of philosophy and law, yet held to an oddly narrow version of the Enlightenment. David Hume and Adam Smith can lay claim to the Enlightenment as much as Kant, and their thinking sets out to control liabilities arising from geography, human vulnerabilities, and our passions. Having more confidence in human grandeur than the Scots, Habermas stuck with Kant as the heir of the Athenians and never doubted the power of reason to build consensus. Those who believe that human beings are “risky” or, like Smith, think “the pride of man makes him love to domineer,” will worry that an adequate account of law must acknowledge the taciturn Spartans amongst us.