The Trump administration’s push to finalize a peace deal with the Taliban over the last week was twice interrupted by deadly explosions in Afghanistan, a reality check that any serious U.S. military drawdown in the war-torn country in no way guarantees a peaceful transition.

Despite the most recent spate of violence and instability, U.S. Special Representative to Afghanistan Zalmay Khalilzad on Tuesday headed to Doha, Qatar to resume talks with Taliban and Afghan leaders “as part of the overall effort to facilitate a peace process that ends the conflict,” the State Department announced.

Details of a peace deal are just emerging and are far from certain, but the prospect of ending the 18-year military presence in Afghanistan has reignited an intense perennial debate over U.S. interests in remaining there.

For now, President Trump seems intent on letting the talks play out, aiming to fulfill his previous campaign promise of ending the war and fending off inevitable criticism from his 2020 Democratic rivals, who largely agree that the U.S. should leave.

Zalmay, the Afghan-born American who served as President George W. Bush’s envoy to Iraq, Afghanistan and the United Nations, briefed Trump on Friday on the status of the talks. Over the last several days, he has also redoubled his efforts to convince all sides to negotiate even after a weekend suicide bombing at a wedding in Kabul that killed 63 people. The Islamic State claimed credit for the deadly attack.

“We must accelerate the #AfghanPeaceProcess including intra-Afghan negotiations,” Khalilzad tweeted Sunday. “Success here will put Afghans in a much stronger position to defeat ISIS.”

One day later, 66 more people were killed in a series of explosions in the city of Jalalabad on the country’s centennial celebration of its independence.

While critics viewed Khalilzad’s Sunday tweet as overly optimistic, it also focuses on the most positive aspect of attaining a deal. Such a pact would allow both the U.S. and the Taliban to focus on further decimating ISIS, which is a small but lethal part of the country’s insurgency.

But skeptics argue that trusting the Taliban is a fool’s errand. Even if the fundamentalist militants are true to their pledge to renounce international terrorists and deny them refuge, other experts fear it won’t be long before they take over the country and reestablish another radical religious regime, as they did in the 1990s.

It’s clear from tweets and statements that Trump wants to be the president that pulls America out of its longest war, but far more nebulous is how much bloodshed and turmoil he’s willing to tolerate in the process, especially with some of his strongest Republican allies in Congress warning against a precipitous withdrawal.

Last Friday, following news of progress in the peace talks, Sen. Lindsey Graham urged Trump “to learn from President Obama’s mistakes.”

“A bad agreement puts the radical Islamist movement all over the world on steroids,” he tweeted. “Be smart, take your time, and listen to your national security team.”

When Trump later tweeted that his administration is making progress and could reach a deal, Graham said he’s “certain that al-Qaeda, ISIS, and other radical Islamist groups are not interested in the war ending.”

In a later tweet, Graham added that the U.S. must have a “robust counterterrorism force with intel capable no matter what the Taliban demands in order to protect the USA.”

That last statement demonstrated at least a willingness to consider the parameters of a peace deal, a shift in the senator’s usually flat rejection of pulling troops from the region.

Other longtime withdrawal skeptics also appear more open to a deal, as long as all parties buy in, agree to allow the Afghan government to share power and commit to a sustained reduction in violence, as ephemeral as that may be.

Michael O’Hanlon, a prominent national security expert and a senior fellow at The Brookings Institution, recently expressed measured hope for the talks’ success, depending on the Taliban’s commitment to a power-sharing agreement with the Afghan government and other details that have yet to be hashed out and made public.

Broad outlines of the initial part of the deal, according to reports, involve cutting U.S. troop levels from roughly 14,000 to 8,000 with the overall foreign troop presence, including from other NATO nations, declining from 20,000 to 12,000. In exchange, the Taliban would agree to fight the presence of al-Qaeda and the Islamic State in their country.

“[T]his deal, insofar as it goes, would be OK,” O’Hanlon wrote last week. “It would hardly merit a Nobel Prize in the first instance, and could in fact fall apart — we should recognize that possibility with eyes wide open. Yet it is still an acceptable risk, if reports of its main parameters are in fact correct.”

The first drawdown of forces, O’Hanlon wrote, would return American and NATO forces to about the same level Trump inherited from President Obama back in early 2017.

The next step, however, is where the rubber would meet the road.

“The looming question would be: How much further would we cut in the event of a deal — and how diligent would we be in a presidential election year, about ensuring compliance with such a deal before carrying out a second big round of reductions?” O’Hanlon told RealClearPolitics.

Non-interventionists who have long pushed to leave Afghanistan brush aside arguments that ISIS could rise up, as it did in Iraq in 2011, if the U.S. were to leave.

“This is an entirely different dynamic,” John Glaser, the director of foreign policy studies at the Cato Institute, told RCP. “Within Afghanistan there’s an ISIS element, a small group known as the Islamic State Khorasan, or ISK, and the Taliban has been literally fighting this group on the battlefield for years. The notion that the group would fill the vacuum and take over is particularly unlikely because the Taliban wouldn’t tolerate it.”

Glaser also disputes concerns that al-Qaeda is once again gaining a safe haven in Afghanistan. He says he never bought into the argument that refuge there gave the 9/11 plotters the ability to carry out their plans. Besides, he says, in the 18 years since the attacks, communication technology has vastly improved so that trying to operate in remote, distant and landlocked Afghanistan is no longer a strategic benefit for terrorists plotting transnational attacks.

“The Taliban desperately wants the U.S. to leave and they’re willing to make certain concessions provided that that mission is accomplished – they don’t want to continually draw fire from the outside by linking up with al-Qaeda and hosting them again,” he argued.

Glaser acknowledges that a bloody civil war could ensue without the U.S. there to keep the relative peace, but said such a clash shouldn’t stop us from leaving if it’s not in our direct national security interest to prevent it.

“If our national security interest is not impacted … to be blunt about it, it’s none of our business,” he said.

But James Carafano, a leading national security at the Heritage Foundation who also served on Trump’s presidential transition team, questions how the U.S. can tell what’s occurring on the ground and whether there’s a threat to U.S. interests without a military presence there to assess it.

“How do we ensure our interests are protected when we don’t have military there and situational awareness over the Taliban?” he asked.

It’s a gamble Carafano believes President Trump shouldn’t make. Afghanistan will be far more stable with the U.S. maintaining a strong presence there, he said.

From a purely political standpoint, starting a drawdown is also risky, Carafano said, because there’s no way to foresee what type of violence will erupt afterward.

“I think its gets [Trump] zero votes. The people who were not going to vote for him are not going to change their mind because he leaves zero troops in Afghanistan. And if you do a deal now, the election is not for a year and a half. If there are really bad outcomes, the Democrats are going to say that you’re at fault.”