WASHINGTON – After 16 years of war in Afghanistan, experts have stoppedasking what victory looks like and are beginning to consider the spectrumof possible defeats.

All options involve acknowledging the war as failed, American aims aslargely unachievable and Afghanistan’s future as only partly salvageable.Their advocates see glimmers of hope barely worth the stomach-turningtrade-offs and slim odds of success.

“I don’t think there is any serious analyst of the situation in Afghanistanwho believes that the war is winnable,” Laurel Miller, a politicalscientist at the RAND Corp., said in a podcast last summer, after leavingher State Department stint as acting special representative for Afghanistanand Pakistan.

This may be why, even after thousands have died and over $100 billion hasbeen spent, even after the past two weeks of shocking bloodshed in Kabul,few expect the United States to try anything other than the status quo.

It is a strategy, as Miller described it, to “prevent the defeat of theAfghan government and prevent military victory by the Talibanlink>” for as long as possible.

Though far from the most promising option, it is the least humiliating. Butsooner or later, the United States and Afghanistan will find themselvesfacing one of Afghanistan’s endgames — whether by choice or not.

1. Nation-Building, Minus the Nation

“I’ll tell you what my best-case scenario would be,” said Frances Z. Brown,an Afghanistan expert at the Carnegie Endowment for International Peace.

That, she said, would see the US-led coalition abandon its efforts toimpose a centralized state and instead allow Afghans to build their ownstate from the bottom up.

It would mean accepting a central government that acts more like a horsetrader among local strongmen and warlords. American and allied troops wouldguarantee enough security to sustain the state. Afghans would figure outthe rest for themselves.

Over time, ideally, Afghans might develop a functioning economy, thensomething like real democracy and, finally, peace and stability.

“But what we know from other cases is that this takes generations,” Brownsaid. “So the 18-month time frames we’ve always had for Afghanistan are notrealistic.”

The perpetual occupation necessary for this to work might also doom it.Continued foreign aid incentivizes Afghan elites, who are already on theverge of splintering, to compete rather than come together.

This approach would involve tolerating the Taliban’s presence in ruralareas. And rolling crises would be built into this model, so Afghans wouldhave to hope that they would somehow never derail the decades of progressneeded before lasting change could take hold.

2. Starting Over

If Afghanistan were forced back to square one, it might, some scholarsthink, be able to rebuild itself from scratch.

After all, humanity lived for millenniums in something resembling low-gradeanarchy. Modern nation-states grew out of that chaos only recently.

This would start with the effective collapse of the state and USwithdrawal. Because the Taliban are too weak and unpopular to retake thecountry, as most analysts believe, Afghanistan would splinter.

Out of the ashes, local warlords and strongmen would rise up. Without theUnited States forcing them to take sides in an all-or-nothing war, theymight eventually accommodate one another, and the Taliban. Their fiefs,once stable, could coalesce over years or decades into a fully realizedstate.

Research by Dipali Mukhopadhyay, a Columbia University political scientist,suggests that the warlords would gravitate toward the kind of statebuilding that occurred in medieval Europe over centuries.

Jennifer Murtazashvili, a University of Pittsburgh political scientist whostudies state building and failure, said the process might unfold morequickly and stably in Afghanistan. She has studied rural Afghan communitiesthat outside the reach of the state, have begun reproducing the basicbuilding blocks of one.

But hers is only a theory, untested in modern history.

3. The Somalia link> Model

In a sign of how far hopes have fallen, the war-torn East African countryof Somalia is increasingly being raised as worthy of emulation.

The Afghan government would retreat to major cities. Formally, it wouldswitch to a federal system, as Somalia did in 2012. But power wouldeffectively flow to whichever warlords and strongmen — potentiallyincluding the Taliban — rose up in the countryside.

This would, in theory, combine the first two models. The government couldreconstitute itself as it mediated between local enclaves that would oneday reintegrate with the state.

“This is the outcome we have de facto ended up with, but not in a peacefulsense,” Murtazashvili said. The government is receding and the warlords arerising, but the two are in conflict.

The Somalia model would manage that process of disintegration, likecrash-landing a plane rather than waiting for it to fall from the sky.

It would leave communities to find their own peace with the Taliban, whichsome in remote parts of the country are already doing.

In Somalia itself, this model has found mixed success. Security hasimproved nationwide, but a devolving state has been left unable to root outextremists, who still carry out devastating attacks.

4. A Peace That Satisfies No One

The paradox of peace deals is that, while all sides benefit, each fearsthat it will not do as well as it could — or that its enemies might do toowell. This gives each an incentive to block all but the perfect deal, adynamic so pronounced in Afghanistan that, in 16 years, talks have neveradvanced far enough to make clear what each side considers acceptable.

“I doubt the Taliban has even given any thought at a higher level to what agovernment looks like that it could have a stake in,” said Courtney Cooper,a Council on Foreign Relations analyst.

The fear of losing out is not misplaced. Afghan elites already squabbleover control of ministries and lucrative patronage networks, and theirinfighting grows as those resources shrink. In any peace deal, they wouldneed to surrender many or most of those resources to the Taliban.

The Taliban, too, would probably need to surrender or curtail their hopesfor dominating Afghanistan. That could anger the extremists rising in thegroup’s ranks.

And any US president would risk a political backlash for appearing to usherthe Taliban back into power. Veterans and military leaders might reasonablyask what they had fought for.

The clearest winner of any deal might be the Afghans themselves, but theyare largely at the mercy of political actors for whom peace is risky.

5. A Post-American Civil War

There is a more pessimistic version of the collapse-then-rebuild model inwhich warlords compete until one prevails over all.

Afghanistan itself offers a particularly vivid example of this scenario:After the 1992 collapse of the Soviet-backed government there, the countrywas gripped by a terrible civil war.

If the Americans abandoned the government now in place, that history couldrepeat.

“There is a strong possibility that this county could splinter, and not inconsensual ways,” Murtazashvili said.

That war culminated, in 1996, with one faction prevailing: the Taliban. Itthen sheltered al-Qaida, prompting the US-led invasion and the war stillraging all these years later.

That history, too, could repeat. Research by Barbara F. Walter, a politicalscientist at the University of California, San Diego, has found thatextremists tend to prevail in civil war, and to do better as the war dragson. If the Americans exit Afghanistan, it might not be for long.

6. Perpetual Stalemate

The likeliest outcome may be allowing the status quo to continue, even asall sides suffer under rising violence.

Neither the government nor the Taliban are strong enough to retake control.Outside actors like the United States and Pakistan may be unable to imposetheir vision of victory, but they can forestall losing indefinitely.

Foreign aid can sustain the government, even as its control of the countryshrinks. There is little to stop the Taliban from carrying out ever morebrazen attacks in the capital. The death toll, already high, would probablyrise.

Eventually, the stalemate would almost certainly break, hurtlingAfghanistan into one of its possible endgames. But it is difficult to saywhen.

“It’s hard to think of an analogous case,” said Brown, the CarnegieAfghanistan expert.

Few modern wars have raged this long, this destructively and with this muchoutside intervention. If there is an obvious way out, history does notprovide it.