The Taliban should savor its triumph while it can, for it is unlikely to survive much beyond this fleeting moment of victory. And those countries in the region that are similarly disposed to celebrate America's defeat should also enjoy the moment while it lasts, for the coming collapse of the Taliban is likely to be more a curse than a blessing.

a group of people riding skis on a snowy road: Taliban fighters guard a checkpoint in Kabul© Getty Images Taliban fighters guard a checkpoint in Kabul

That the Taliban is unlikely to outlive the now-defunct Afghan national government (ANG) by much might seem a far-fetched claim. But the history of the movement - and that of the mujahedeen, which defeated the Soviets and their puppet regime in the late 1980s and early 1990s respectively - strongly suggests that this will almost certainly be the case.

Since its inception, the Taliban has been more a constellation of factions and tribes, drawn from different ethnic and linguistic groups, than the unitary rational actor it is often portrayed to be.

In this, it is no different than either the coalition of warlords that governed Afghanistan directly from 1992 to 1996 or the one that governed Afghanistan through the "state" created by the U.S. in the aftermath of the 2001 invasion. But it has always had two advantages over those two ruling coalitions.

To begin with, the Taliban has always had a clerical command-and-control infrastructure that transcended without displacing or effacing - the tribal, linguistic and communal identities of its constituent elements. But perhaps even more importantly, since 2001 the Taliban has been able to exploit one of the defining elements of Afghan national identity - resistance to foreign occupiers - to override factional differences and maintain a robust political coalition.

These two unifying factors have always given the Taliban a clear advantage over an Afghan national government that was similarly divided but never able to tap into the religious or nationalist sentiment to anything like the same degree. They gave the Taliban a decisive advantage in 1996, when it took control of most of the country, and again after it reconstituted in the early 2000s and began challenging the newly minted ANG beginning in earnest in 2006.

It was these two factors that allowed it to gain the strategic upper hand during the final years of the George W. Bush administration and again in 2015 as President Obama began his post-surge drawdown.

Now, however, one of those unifying factors has evanesced. With the withdrawal of the American "occupier" and the defeat of its Afghan client state, some of the glue holding the Taliban together will soon dissolve.

To be sure, the victors are likely to bask in the afterglow of having expelled the foreign invaders for some time yet. But, if the experience of the victorious mujahedeen in the early 1990s is any guide, that is not likely to last long. Nor is it likely to prove sufficient to contain the centrifugal tendencies within the Taliban coalition. Perhaps the hierarchical command-and-control structures built up over the past three decades will be sufficient to hold the movement together. But then again, maybe they too will wither now that the war has been won, further accelerating the tendency toward fragmentation.

And that prospect - of division leading to dissolution - has several implications for Afghanistan's regional neighbors.

First, it raises the prospect of civil war. It should be remembered that this is precisely what happened in the aftermath of the mujahedeen victory over the USSR three decades ago. In that case, once the common foe was vanquished, the various tribal, communal and linguistic factions turned on each other - and on the Afghan people.

The result was a period of chaos and conflict that ultimately gave rise first to the Taliban insurrection and then to the first Taliban emirate. Absent the U.S., it is reasonable to assume that the disparate parts of the Taliban coalition - long held together precisely by the American presence - will similarly turn on each other, vying for their share of the spoils of victory even to the point of armed conflict.

Second, should this happen, it raises the prospect of several disasters that are likely to spill over Afghanistan's borders - all to the detriment of its regional neighbors. These include a number of humanitarian crises, all culminating in destabilizing refugee flows that will be most unwelcome in Pakistan, Tajikistan and Iran, among others.

Third, if the Taliban splinters in the post-victory scramble for advantage, it raises the prospect of a single Afghan state being replaced by a patchwork of regional statelets overlaid with pockets of ungoverned or contested spaces.

In such an arrangement, even if there is something approximating a Taliban-dominated national government, its writ is unlikely to run much beyond Kabul. Whatever promises that government might make, it simply won't be able to keep them. This is unlikely to prove conducive to foreign investment of the type associated, for example, with China's Belt and Road Initiative. And it is likely to seriously complicate the imminent scramble for Afghanistan's vast mineral wealth.

Fourth, if the Taliban fragments or if parts of the country manage to resist the current onslaught, there will be no such thing as Afghan foreign policy. Rather, there will be a variety of statelets, each with its own interests and priorities, and each conducting its own foreign policy.

The result will be a situation in which Tajik militants of Jamaat Ansarullah, Uzbek groups like Katibat Imam al-Bukhari, Uighur fighters of the Turkestan Islamic Party from China's Xinjiang region and others all become the core of new ethnic statelets, each conducting its own foreign relations and perhaps taking steps to liberate their oppressed compatriots in neighboring countries.

Whatever the specific outcome, it is a mistake to assume that the future of Afghanistan's domestic politics or foreign policy will be determined by a unified Taliban government more or less rationally pursuing its interests. Given the chaos and conflict that are likely to ensue, those who are currently celebrating the fall of Afghanistan may soon come to wish for the good old days when the Americans kept at least a partial lid on things.

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