Most of those decrying the imminent termination of America’s military mission in Afghanistan tend to do so in terms of the logic of liberal internationalism. According to this logic, the end of the Cold War created a new international order defined by unipolarity (with the United States as the sole superpower) and the ascendancy of an essentially liberal set of norms, rules and institutions that it was believed would deliver both perpetual peace and universal prosperity.

With the birth of the “unipolar moment,” however, new threats also appeared. While the existential menace of Soviet hegemonism had disappeared, the lesser-but-still-worrying dangers posed by “rogue states,” “global terrorism” and “state failure” replaced it in the geopolitical imagination of the American foreign policy establishment.

In turn, this gave rise to a new grand strategy – liberal internationalism – the main thrust of which was that U.S. military primacy and unmatched soft power resources should be used to uphold, police and defend the newly minted “Liberal International Order” (LIO). A replacement for the Cold War grand strategy of containment, like that earlier geopolitical framework liberal internationalism became the overarching vision guiding U.S. foreign and defense policy.

Viewed against this backdrop, the two decade-long U.S. mission to Afghanistan makes a great deal of sense — at least as an aspiration. Illiberal forces had attacked not just the United States, but two of the principal icons of the LIO, the World Trade Center and the Pentagon. Moreover, they had done so from beyond the frontiers of the liberal world — from the illiberal and therefore dangerously retrograde country of Afghanistan. From the perspective of liberal internationalism, a U.S. invasion to extirpate al Qaeda and its Taliban patrons, followed by a campaign to transform Afghanistan into a functioning liberal democracy, made perfect sense. Indeed, viewed through the lens of liberal internationalism, it was the only option that made sense.

Conversely, when viewed from the perspective of liberal internationalism, the now-imminent U.S. withdrawal looks like a serious mistake. For not only does it augur the retrocession of Afghanistan to a place beyond the liberal pale – with all that that entails for those Afghans who threw their lot in with the U.S. and other forces of liberalism – but it also signals a failure of the U.S. to uphold and defend the LIO itself. Both sentiments are on prominent display in the recent hand-wringing about the “loss” of Afghanistan. 

But there is another way to look at the U.S. withdrawal. If one rejects the nostrums and shibboleths of liberal internationalism and adopts instead a more realist perspective, concerns about threats to the LIO – now increasingly re-branded as the “rules-based order” – and the loss of Afghanistan to the forces of illiberalism quickly fade. And as those concerns fade, a strategic upside begins to come into focus. Most immediately, this upside takes the form of a decisive end to the flow of American blood in, and treasure to, Afghanistan. As importantly, however, the upside to a U.S. withdrawal from that country also takes the form of destabilizing Russia’s southern flank and thus weakening Moscow’s ability to pursue its great power ambitions in both Central Asia and Europe.

How so?

Well, consider the likely outcome of the U.S. withdrawal — the collapse of the Afghan national government and the emergence of a Taliban emirate in its place. If this were to happen, and the Taliban – like so many revolutionary movements – were to seek to export the revolution, this might well destabilize neighboring Central Asian states.

Tajikistan is already experiencing the tremors that might well presage a regional geopolitical earthquake and has been forced to call on Russia and other members of the Collective Security Treaty Organization (CSTO) – a post-Soviet, Russian-dominated military alliance – to provide assistance in dealing with security challenges emerging from neighboring Afghanistan. Russia seems likely to respond by augmenting its military forces already deployed to its base at Dushanbe, the country’s capital. 

Should this tremor in fact prove to be the harbinger of more general unrest in Central Asia, Russia will be required to devote more – perhaps considerably more – military resources to the region. For should any of the CSTO member states fall to Taliban-aligned movements emboldened by the fall of the Afghan national government and the “defeat” of the United States, Russia’s status as regional security-guarantor and hegemon will be cast into considerable doubt.

But even if the Kremlin’s worst-case scenario does not come to pass, continued Taliban-fomented unrest throughout the region will still demand Russia’s increased attention. Quite apart from the region’s economic importance – it is an important source of cheap migrant labor for the Russian economy – Central Asian instability and insurgencies have a way of spilling over into Russia proper. And we shouldn’t forget that Russia still sees the region as part of its near-abroad — a space that it believes it is entitled to dominate by right. 

For all of these reasons, Moscow simply cannot afford the luxury of sitting idly by while the Taliban stir up trouble in the region. If Kabul falls, Russia will be drawn ever more deeply into an increasingly unstable Central Asia. And while the likelihood of it being drawn once again into the graveyard of empires is remote, that of being drawn into the immediate environs of that graveyard is considerable. 

And that is why, from a realist perspective, the U.S. withdrawal from Afghanistan does not constitute a strategic disaster. In a new era of great power competition, preventing any country from dominating the heart of Eurasia should be a goal of American grand strategy. A Taliban-dominated Afghanistan, emboldened by its victory over the United States to take its insurrection on the road, is likely to undermine Russian efforts – and perhaps Chinese ones, too – to achieve such dominance. While this will doubtless prove most unwelcome in Moscow, it should be viewed much more favorably in Washington. Whether it will or not largely depends on whether the American foreign policy establishment is finally ready to move beyond the liberal internationalism of yesteryear and embrace instead the timeless logic of balance-of-power realism.    

Andrew Latham is a professor of international relations at Macalester College in St. Paul, Minnesota.