The Vietnam War in particular seemed to vindicate Lippmann: the effort to hold an untenable position in Southeast Asia imposed horrendous costs on the United States, nearly unraveling its larger strategic position and causing severe unrest at home. Meanwhile, a forty-year arms race required the United States to build an unprecedented peacetime military establishment while enduring repeated crises that threatened to bring on nuclear catastrophe. Containment did prove to be a form of “trench warfare,” requiring a vast investment of resources and leading to many of the perils Lippmann had identified. And if Kennan had initially bridled at Lippmann’s critique, this “architect of containment” quickly lost faith in his own strategy—and began to emulate his erstwhile intellectual opponent in calling for a de-escalation of the Cold War.

In 1948–49, Kennan privately urged the U.S. government to seek a mutual superpower withdrawal from Central Europe, meant to avoid a “congealment” of the strategic faceoff there. As a disillusioned former official in the 1950s, he made the same proposal publicly, in hopes of breaking a bipolar status quo that was becoming all the more dangerous as nuclear arsenals grew. During the 1960s and 1970s, a series of presidents would try to negotiate something along the lines of what Lippmann had recommended—a détente that would reduce tensions, ease the danger of war, and drain the Cold War of its ideological passion.

Yet if Lippmann had looked prescient in the wake of Vietnam, it was ultimately Kennan—the 1947 version, anyway—who proved more prophetic. The Cold War ended not as Lippmann had anticipated, in mutual de-escalation, but as Kennan had initially predicted—in a Soviet mellowing that produced concessions the West had been seeking for decades, and then a Soviet breakup that eliminated the enemy altogether. The Soviet system failed, moreover, due to many of the built-in irrationalities and obstacles to reform that Kennan had identified.

Containment often appeared to be failing up until the moment when it succeeded completely. So why did Lippmann, who got a great deal about the Cold War correct, ultimately get the biggest issues wrong? The answer reveals a great deal about long-term competition and what made the United States, during the postwar era, so capable in waging it.

First, Lippmann made the error of forgetting that the competitive weaknesses of democracies are often more evident—but less damaging—than those of autocracies. A longtime observer of American politics and policy, Lippmann easily spotted the ways in which the perpetual low-grade disorder of the U.S. system might undermine the country’s aptitude for long global rivalry. Yet he missed the fact that the dynamism of the American economy and the legitimacy of American democracy actually equipped the United States well for a geopolitical war of attrition. And he failed to see, as the Sovietologist Kennan had, the deep-seated frailties of the adversary. The fragility of the Soviet growth model, the disillusionment of its people in the empty slogans mouthed by party apparatchiks, and the difficulty of political and intellectual renewal within a vicious yet sclerotic polity were flaws that could be concealed, for a time, by a deliberately opaque system. Yet they would eventually reveal themselves in ways that challenged the Kremlin’s competitiveness and ultimately its survival. The everyday failings of the American system were there for all to see. The more profound debilities of the Soviet system only became evident with time.

Second, American democracy was far better suited to rivalry than Lippmann had appreciated. Yes, electoral politics and separation of powers made American policy less purposeful and more volatile than Lippmann (and Kennan) would have liked. But the Cold War showed that democracies could wield powerful strategic advantages over authoritarian competitors. America’s combination of democratic politics and free-market economics generated a degree of wealth and innovation that a stifling Soviet system could never match. It made the United States better suited to managing alliances—with all the give-and-take that requires—than Communist leaders used to ruling by decree could ever be. Most important, it ensured that the United States had built-in mechanisms for the strategic course-correction—elections and changes of administration—that are vital in any long rivalry. Democracy was, from time to time, a tactical disadvantage, but it was a long-run strategic blessing for the United States.

Third, Lippmann failed to foresee how a successful strategy might combine purpose with flexibility. Containment was never a fixed collection of policies: It was a basic concept that provided direction while permitting flexibility and strategic choice. In the late 1940s, for instance, the Truman administration chose to hold the line in Western Europe, which mattered tremendously to the balance of power, but not in China, which at that point did not. Over the subsequent decades, U.S. leaders would periodically shift the precise mix of tools and policies used to contain Soviet influence—investing more or fewer resources, expanding or contracting America’s obligations, adjusting the role of nuclear weapons in the free world’s defense. And when the Vietnam War showed that containment was becoming unsustainable, the United States shifted to a strategy that involved limiting its liability in Third-World conflicts, using covert action to punish Soviet overextension, and steering the arms race into new, high-tech areas to show that Moscow could not forever survive competition with Washington. This protean nature of containment frustrated Kennan, who saw “his” strategy evolve in ways he neither expected nor desired. But that quality allowed containment to endure and triumph.

Fourth, Lippmann underestimated the extent to which the best American strategies combine ideology and realpolitik. The ideological dimensions of containment were critical: Absent an emphasis on defending American values and a free way of life, U.S. policy never would have commanded sustained public support. Nor would it have been as appealing to America’s most important allies: those countries, particularly in Western Europe, linked to the United States not just by common geopolitical interests but by common political values. Yet the emphasis on democracy versus authoritarianism, capitalism versus communism didn’t prevent American officials from cutting realpolitik deals with communist devils—whether Yugoslavia’s Josip Broz Tito or China’s Mao Zedong—where U.S. interests required. Much less did it prevent them from displaying an extremely flexible morality when it came to fighting communism in the Third World. Ideology was a useful guide to Cold War statecraft; it was rarely a straitjacket.

Fifth, Kennan divined that successful diplomacy would follow, rather than precede, a policy of strength. In part, this was because ideology played a bigger role in Soviet policy than Lippmann admitted: for decades, Soviet leaders really did think socialism was destined to bury capitalism. In part, it was because Kremlin leaders could conceivably see a path to victory in the Cold War into the 1970s. It wasn’t until the cancers of the Communist system began to metastasize, a free world that the United States had protected and nurtured began to leave the Soviet Union behind, and Washington dramatically turned up the pressure on Moscow during the 1980s that a new generation of Kremlin leaders realized that the only way out of the Cold War was to deescalate it on American terms. The superpower struggle did end in a diplomatic settlement of sorts—a negotiated Soviet surrender on nearly all issues of dispute. But that settlement came after, not before, a long period of competition.

These issues related to a final point: that even prolonged, dangerous competition can be a way of avoiding something worse. In focusing on the balance of power, Lippmann miscalculated the balance of evils. Although the columnist was hardly naïve when it came to the nature of the Soviet regime, he focused his critique on the evils that containing that regime would entail—proxy wars, distasteful partnerships, massive expenditures, dangers of war. Many of those problems did materialize, but looking back, it is hard to argue that they were greater than the evils of pursuing a diplomatic settlement that would have provided only the illusion of peace, or of permitting the emergence of a world in which the power of a terrible totalitarian regime was not contained. Containment was indeed a highly unappealing strategy—just not compared to the realistic alternatives.

THERE ARE myriad differences between today’s U.S.-China rivalry and the Cold War. China is as integrated into the global economy as the Soviet Union was isolated from it. Key aspects of the U.S.-China rivalry—the value of possessing vast quantities of digital data and the struggle over the world’s telecommunications networks, to give two examples—lack obvious Cold War parallels. Yet the United States is once again entering into a dangerous, prolonged competition against a potent authoritarian rival, and once again it must define a strategy that will carry it through that trial. Here, the Kennan-Lippmann debate and the subsequent trajectory of containment offer useful insights.

For starters, no one should view the return of great-power competition with enthusiasm. It is tempting to look back on the Cold War as an epochal triumph of American statecraft and a bloodless, glorious victory over a tyrannical rivalry. But it wasn’t for nothing that Lippmann and others were so skeptical of containment. That strategy incurred high costs and extreme dangers over many decades; it led the United States into moral and strategic traps on the global periphery, where the superpower rivalry was rarely glorious or bloodless; it taxed America’s democratic system and periodically empowered profoundly illiberal influences, notably McCarthyism, at home.