If there is an international order, it seems to be in crisis. Vladimir Putin boasts of new nuclear weaponry impervious to NATO defenses and is accused of ordering an assassination on British soil; Xi Jinping has been relieved of presidential term limits and is positioning China as an alternative to Western liberalism; and Kim Jong Un has transformed himself from the frequently lampooned leader of a pariah state into a diplomatic player on a world scale. In a recent Op Ed in The New York Times, Bret Stephens warned of the rise of “Dictatorship, Inc.”an “axis of evil” that includes Russia, China, Korea, Syria, and Iran. His prescription was a renewed “belief in what used to be called the free world.”

Meanwhile, in the ten years since the financial crisis, the Western core of the global order has fractured internally, with movements of the right and left increasingly skeptical of the viability of the European and Atlantic communities. The election of an “America First” candidate in 2016 seemed to signal a U.S. retreat from the community of shared strategic interests associated with the “West.” Some now look for leadership in Europe. In a September interview on MSNBC, Hillary Clinton declared Angela Merkel to be “the most important leader in the free world.” A few months later, the French commentator Nicolas Tenzer wondered whether the mantle of free world leadership might be assumed by Emmanuel Macron.

But while dangers abound, defenders of the current order seem to have difficulty defining the system they seek to preserve. What justifies the continued existence of a transatlantic alliance binding the U.S. to Western Europe, and how does it relate to a broader global order? What is the free world that Stephens wants to revive and that Merkel and Macron have been nominated to lead? What is being challenged by foreign dictators and anti-establishment movements? How was the construction of the current order originally justified and in whose name should it be preserved?

The term “free world” emerged in the late 1930s and early 1940s as an anti-fascist rallying cry. In the spring of 1938, a group of French writers and politicians, including former Prime Minister Édouard Herriot, founded a magazine called “Monde libre” (Free World) in an attempt to foster greater solidarity among democratic nations. Four years later, at the height of WWII, the American Vice President Henry Wallace emphasized the existential nature of the global conflict in a speech to the U.S.-based International Free World Association: “This is a fight between a slave world and a free world. Just as the United States in 1862 could not remain half slave and half free, so in 1942 the world must make its decision for a complete victory one way or the other.” Later that year, the Oscar-winning Frank Capra propaganda film “Prelude to War” illustrated the point by showing two spheres side by side, one black and one white, one a “free world” and the other a “slave world,” each encompassing an entire globe. The message was clear and much repeated: the planet had become small and interdependent; the forces of slavery had set out to conquer the world; and the fate of freedom everywhere depended on their defeat.

The Allies prevailed, but U.S. leaders soon declared a new war of the worlds. The Soviet Union’s westward expansion and communism’s ideological appeal seemed to constitute a serious challenge to the postwar order envisioned by the United States. In 1950, National Security Council Report 68—a major internal statement on U.S. foreign policy—stressed the threat posed to the “free world” by “slave society.” This time the borders between the two worlds were mostly static and easily mapped.

The Cold War incarnation of the “free world” envisioned a neatly Manichean globe with membership and moral attributes clearly defined on each side. Policymakers constructing the Western alliance in the middle of the twentieth century embedded it within this planetary perspective. The U.S. justified its foreign entanglements as the responsibilities of Free World leadership; British MPs proclaimed their country’s indispensability to the “free world” as a bridge between what they declared were its principal parts—the U.S., Europe and the Commonwealth; France demanded, and received, official support for defending the “free world’s” interests in Indochina; the Three Powers formally extended “free world” membership to West Germany in a 1952 convention; Washington consistently backed European federation in an effort to secure greater “free world” solidarity; and NATO publicly and privately declared its mission to be the defense of the “free world” within a larger network of “free world alliances” that eventually encompassed the Baghdad Pact (including Iran, Iraq, Pakistan, Turkey and the UK), the Rio Pact (originally including much of the Americas), the Australia, New Zealand, and United States Security Treaty (ANZUS), and the Southeast Asia Treaty Organization (SEATO).

The “free world” framework proved remarkably successful in justifying a cohesive Western alliance and U.S.-dominated global order of unprecedented power and scope. But the notion of the “free world” was fraught with contradictions that eventually led to its disappearance as an essential legitimizing concept. The idea that the “free world” was engaged in an immediate, global, and existential crisis came into conflict with the increasingly static nature of the Cold War. The national freedom (by definition) of the “free world’s” component parts made U.S. leadership a delicate affair and provoked jealousy among policymakers of the Kremlin’s seemingly total control of the Communist “monolith.” And the inclusion, by default, of all non-Communist nations within the Free World created tension between a Western core and an Afro-Asian periphery of the “uncommitted” and the “underdeveloped,” the “newly-emergent” and the “non-aligned,” whose occasional rejection of Free World membership American leaders interpreted as a form of false consciousness.

Toward the end of the 1960s, many of the fundamental assumptions of the “free world” framework no longer seemed tenable. The Sino-Soviet split divided the supposedly monolithic “slave world” into two competing camps, Communist world conquest appeared unlikely, and the realities of Soviet life seemed increasingly distant from the Orwellian and Arendtian images of totalitarianism. At the same time, a growing countercultural movement in the West questioned the freedom of the “free world” from within; a resurgent Europe began to reassert its foreign policy independence (most notably in West Germany’s efforts to establish a relationship with East Germany and France’s departure from NATO); and many former colonies and developing states acquired recognition as a “Third World” of their own, complicating the idea of a binary globe. By the early 1970s, the term “free world” had almost completely disappeared from political discourse and government documents across North America and Western Europe. Reagan would later revive a rhetoric of anti-communist freedom, but in a more unilateralist, American key.

The concept of the “free world” was discarded, but its Western core remained intact, unchallenged by any real alternative and hegemonic enough—economically, culturally, and militarily—not to worry about justifying its continued existence. For the remainder of the century, its foreign policy focused on the export of neoliberal economics, human rights, and democracy to the newly-identified “Third World” and, following the collapse of the USSR, to the former communist East. The European Union was constructed as a separate economic entity, but remained unquestioningly under the American defense umbrella. Together, the EU and NATO expanded eastward to include many of the former “captive nations” of the Cold War, even as Russia itself remained an awkward institutional adversary. The Western liberal system, its champions declared, was surging across the world, and History itself had come to an end.

This vision remains unfulfilled. The universalizing Western order has encountered increasingly powerful resistance from without. Perhaps more important, its core institutions and ideological tenets have been challenged from within. Across Europe and North America, traditional parties have been captured by outsiders or have been threatened, and at times supplanted, by anti-establishment alternatives. All of these forces, whether on the socialist Left or the anti-immigrant Right, accuse the liberal order of failing to represent the people and share an antipathy toward European and Western international institutions. The assumed community of fundamental interests binding the countries of North America and Europe has been called into question. The result has been a crisis in the legitimacy of the Western core of the former “free world.” What is its ultimate purpose and who does it define itself against? Defenders of the North Atlantic nexus, unable to respond to the first question, have rushed to propose an answer to the second. A common external enemy, they seem to believe, would explain internal divisions in the present and require continued cohesion in the future.

China represents one potential outside to the West’s inside. It is a former Cold War foe, a powerful geopolitical competitor, and a self-confident civilizational alternative. But China is perhaps too distant, both geographically and culturally, to serve as a readily comprehensible antagonist. More important, the Western economic order, and the American dollar in particular, depends on Chinese goodwill far too much for statesmen to risk antagonizing Beijing with reckless rhetoric.

After 9/11, Islam seemed to reprise its role as the traditional Other on the borders of a Western, Christian civilization. President George W. Bush’s War on Terror sought to identify “radical Islam” as the common enemy of a willing coalition. But terrorism turned out to be too diffuse and far-flung, an enemy without headquarters, difficult to discern or defeat. A never-ending peripheral engagement unconnected to any conceivable large-scale threat proved unconvincing as grounds for increased Western solidarity.

Instead, Islam became an internal challenge, raising questions about immigration and assimilation, identity and culture, borders and security. Rather than reinforcing a broader Western cohesion, the perception of Islam as an alien force has given rise to right-wing movements seeking to dismantle the European and Atlanticist liberal system in the name of an older and narrower national identity.

The antagonist best suited to provide the western world with a renewed raison d’être is its original Cold War enemy. Russia can be kept comfortably outside of the West (unlike Islam), but looms large as a historically familiar foe just beyond its border (unlike China). It is militarily strong enough to seem legitimately, and perhaps existentially, threatening (unlike Islam), but is not so economically massive as to give rise to any real worry about causing offense (unlike China). Finally, Russia is indeed interested in supporting the dismantling of an alliance that was set up in opposition to it.

But Russia too, is a problematic enemy. In the current Western construct, it represents nothing beyond aggression, subversion, and the pathological personality of Putin. Its objectives are all described in the negative. It seeks to sow division and destroy democracy, but contains no ideological substance remotely comparable to communism. When, in 1950, Eisenhower called on American citizens to “fight the big lie with the big truth,” the communist propaganda he hoped to counter contained a coherent message that appealed to a broad section of Western intellectuals. Today’s “fake news” is generated by bots and aims for no discernible ideological consistency. An enemy with no positive content of its own makes for an uncertain opposite number.

The precise nature of a Western alliance encompassing members of NATO and the EU, and centered on the U.S., the U.K., Germany, and France, is similarly difficult to describe. The “free world” framework within which it was created in the 1950s may have been morally simplistic and rife with the contradictions that ultimately contributed to the concept’s disappearance, but it also provided a clear formula for determining who was inside and who was outside and on what grounds. The Western core of the former “free world” remains, but its institutional foundations and conceptual legitimacy have come under fire. Who, precisely, does it represent? And what, if anything, should it be called? The defense of an uncertain construct against an empty enemy makes a final victory difficult to imagine.