US President Joe Biden faces challenges (Image: AP/Andrew Harnik)

US President Joe Biden’s decision to withdraw all American troops from Afghanistan by September 11 shouldn’t come as a surprise. Since he took office in January, Biden has telegraphed his intention to leave Afghanistan sooner rather than later, formally bringing an end to the 20-year war. In a Tuesday briefing, the administration indicated its plans to end military operations while keeping a focus on the ongoing Afghan peace process.

In reality, the new withdrawal plan complicates US efforts to broker peace between the Afghan government and the Taliban. But if there is any chance of peace in Afghanistan, the five months before the completion of the withdrawal will be critical. Peace prospects will hinge on how the Taliban react to two key dates: May 1, the previously agreed deadline for US withdrawal, and September 11, or whenever the last US soldier has departed.

Biden’s withdrawal decision should, in theory, advance the peace process: an agreement between Washington and the Taliban reached in Doha in 2020 called for all US troops to leave Afghanistan and ended Taliban attacks on US forces. But the Doha accord stipulated that US troops leave by May 1, and the Taliban have repeated that all US soldiers still must be out by that date. Moreover, the Taliban will enjoy a battlefield advantage when the withdrawal is complete that gives the group little incentive to remain committed to peace talks.

The Taliban have already insisted on a strict interpretation of the May 1 withdrawal clause. The worst-case scenario is Taliban members conclude the US has violated the Doha deal by staying past the deadline and tear up the agreement, relaunching attacks on US forces and rejecting the Afghan peace process. In an indication of the Taliban’s fixation on US withdrawal, the group’s spokesperson tweeted hours after news of Biden’s plan broke that the Taliban will not participate in any Afghanistan conference “until all foreign forces completely withdraw from our homeland”.

The Biden administration hopes to avoid this scenario by pointing to the fact that its withdrawal will begin before May 1 and will be done by September 11. It hopes the Taliban will find this brief extension, with a specific end date, more palatable than an open-ended one. Washington is also banking on the fact that the Doha deal has given the Taliban the global legitimacy it seeks by locking the insurgents into an internationally recognised agreement. If Taliban leaders rip up the accord and relaunch attacks on US forces, the group risks losing that legitimacy.

The Taliban have given little indication of their plans, though a former Taliban minister told the Daily Beast that by extending its presence, the US “has shattered the Taliban’s trust”. On Wednesday, a Taliban spokesperson tweeted, “if the agreement is breached and foreign forces fail to exit our country on the specified date, problems will certainly be compounded and those whom failed to comply with the agreement will be held liable”. At a Tuesday briefing, a senior Biden administration official said if the Taliban do attack US forces, “we will hit back hard, and … we will hold them accountable for that”.

But come September, US firepower will no longer be an option to deploy against the Taliban. Once the US has withdrawn, the Taliban have a strong incentive to focus their full attention on the battlefield. Turning their back on the peace process would give the insurgents an opportunity to finish off a war they have long seen as theirs to win. The withdrawal will eliminate the threat of US airpower, a potent tool preventing Taliban forces from advancing into cities. The departure of the 7000 remaining majority-NATO forces in coordination with the US drawdown will deliver another blow to Afghan troops, who will no longer receive US training and advice. The beleaguered forces, already reeling from record-level fatalities, will face a major challenge to morale.

From the Taliban’s perspective, the appeal of turning their full attention to the fight against the government after US withdrawal is only enhanced by a peace process that appears set up to fail. The Afghan government and the Taliban are worlds apart on many issues, from how to prioritise the negotiating agenda to their preferred post-war political system.

As currently envisioned, the peace process aims to produce a power-sharing agreement that ends the war. But Taliban leaders reject democratic elections and the principles of civil and human rights enshrined in the Afghan constitution and favor draconian interpretations of Islamic law. The insurgents already seem to threaten the voices deemed unwelcome in their preferred political system. In recent months, a horrific campaign of targeted killings against civil society has convulsed Afghanistan, with election activists, female judges and media workers targeted. No group has claimed responsibility, but a NATO official recently estimated in a private briefing that the Taliban is behind about 80% of them.

The Taliban could easily decide they are better off fighting for complete power than negotiating for partial power within a system that they repudiate. They have already rejected the peace plan advanced by Afghan President Ashraf Ghani, and they have declined to endorse one proposed by the Biden administration.

The US has five months to keep the sputtering Afghan peace process alive. Securing a comprehensive ceasefire is an important first step. Washington should refuse to fulfil its remaining obligations to the Taliban under the Doha deal, including the release of Taliban prisoners and the removal of the Taliban from United Nations sanctions lists, until the Taliban agrees to a ceasefire. It should enlist regional governments and the broader international community in this effort. The US needs to deliver a strong message: if the Taliban reject a global consensus supporting a ceasefire, they jeopardise their own legitimacy.

Another key step is setting up an interim government to oversee the peace process. Ghani rejects this proposal, likely because it would end his presidency. But the Taliban are more likely to agree to an extended ceasefire with a transitional government in place — and one that doesn’t include Ghani, who they refuse to work with. Washington should threaten to reduce future financial assistance to Kabul if Ghani doesn’t agree to one, reiterating that peace — not concerns about political survival — is in Afghanistan’s national interest.

None of this will be easy. The Biden administration acknowledges as much: an annual assessment from the Office of the Director of National Intelligence released on April 9 concludes the prospects for peace “will remain low during the next year”.

Afghanistan’s fate will ultimately be left in the hands of Afghans. But Washington owes it to them to do its best over the next few months to ensure it doesn’t leave them high and dry on September 11. The US will soon wrap up its longest foreign war. For Afghans, the war has lasted twice as long, and most of them don’t have the luxury of escaping it.

Michael Kugelman is the writer of Foreign Policy’s weekly South Asia Brief. He is the Asia Program deputy director and senior associate for South Asia at the Wilson Center in Washington. Twitter: @michaelkugelman