Over the past 50 years, the philosopher who’s played the most significant role in the cultural life of the United States isn’t Richard Rorty, Jerry Fodor, or Martha Nussbaum, but rather Immanuel Kant. This is largely because of his impact on postwar trends in moral philosophy. Kant’s influence during this period coincided with the rise of ethics as a dominant concern in political theory. John Rawls, Ronald Dworkin, and Thomas Nagel are among the most prominent examples of this widespread tendency. It is possible to exaggerate the novelty of this development; after all, questions of morality have always had a place in reflective debate about politics. Yet the strict subordination of politics to morals in recent decades does represent some kind of departure, or at least a return to a style of Kantian thought that had long been out of favor. Compared with current tendencies in political philosophy, normative inquiry was of marginal importance to the leading political thinkers in the first half of the 20th century, among them Max Weber, Otto Bauer, Michael Oakeshott, John Maynard Keynes, Friedrich Hayek, Raymond Aron, and Hannah Arendt.
I don’t mean to suggest that these thinkers took no interest in human values. Because politics is a product of the struggle over values, political thinking can hardly avoid such a pivotal issue. But there’s a difference between the study of human preferences and attachments and a preoccupation with an ideal theory of value. An ideal view of politics begins with a normative approach to power; it operates with a purely moral conception of how social and political relations ought to be organized. From this perspective, as Kant proposed in an essay he wrote in 1793, the rules of prudence ought to be sacrificed to the dictates of moral law. Dishonesty in politics might well be advantageous, to take one example, but from where Kant was standing, it could never be morally right.
The normative turn in political philosophy has overlapped with the rise of moralism in certain areas of US policy, most obviously in international affairs. This tendency came to prominence in the early years of the new millennium, as Dick Cheney and George W. Bush set about reconceiving the international order in terms of ideal values. Because democracy was now regarded as a “universal” norm, it was thought that it might systematically replace dictatorships across the globe: With the aid of strategic military intervention, authoritarian regimes would fall like dominoes throughout the Middle East. In line with this approach, practical obstacles were wished away under the influence of a crusading righteousness.
In general terms, the retreat of political philosophy onto the terrain of abstract morals has exacted a heavy cost. The loss has been twofold. First, a narrow focus on the absolute obligations of duty is prone to disregard the tangible desires of human beings. Second, an exclusive interest in what is unconditionally justified can lead to the suspension of all concern with what is beneficial. In the decades before Kant set about converting political theory into a branch of moral inquiry, the great Scottish philosopher and historian David Hume had been cultivating what amounted to the opposite perspective. Hume’s program had two core features: It examined what actually motivated people instead of what they ought to do in principle; and it calculated the advantages that emerged from a course of action as opposed to evaluating its intrinsic merits. This approach might be seen as a criticism of Kantianism before Kant. More accurately, it can be viewed as a rejection of Stoicism, elements of which were later revived by Kant in combination with strands of Lutheran pietism. It is right, in Kant’s analysis, that the Stoics were ultimately deemed deficient, but they were to be praised for equating happiness with “purely moral perfection.”