DOHA, QATAR >> The United States signed a peace agreement with Taliban militants today aimed at bringing an end to 18 years of bloodshed in Afghanistan that began after 9/11 and allowing U.S. troops to return home from America’s longest war.

This historic deal, signed by chief negotiators from the two sides and witnessed by Secretary of State Mike Pompeo in the Qatari capital of Doha, could see the withdrawal of all American and allied forces in the next 14 months and allow President Donald Trump to fulfill a key campaign pledge to extract the U.S. from “endless wars.” It sets the stage for intra-Afghan peace talks to begin by March 10 during which a permanent ceasefire will be negotiated and the Taliban agree to meet with all factions.

Under the agreement, the U.S. would draw its forces down to 8,600 from 13,000 in the next 3-4 months, with the remaining U.S. forces withdrawing in 14 months. The complete pullout would depend on the Taliban meeting their commitments to prevent terrorism, including specific obligations to renounce al-Qaida and prevent that group and others from using Afghan soil to plot attacks on the U.S. or its allies. The deal does not, however, tie the U.S. withdrawal to any specific outcome from the all Afghan talks, according to U.S. officials.

“We will closely watch the Taliban’s compliance with their commitments, and calibrate the pace of our withdrawal to their actions. This is how we will ensure that Afghanistan never again serves as a base for international terrorists,” said Pompeo. He acknowledged that the road ahead would be difficult but said the deal represented “the best opportunity for peace in a generation.”

At a parallel ceremony in Kabul, U.S. Defense Secretary Mark Esper and Afghan President Ashraf Ghani signed a joint statement committing the Afghan government to support the U.S.-Taliban deal, which is viewed skeptically by many war-weary Afghans, particularly women who fear a comeback of repression under the ultra-conservative Taliban.

President George W. Bush ordered the U.S.-led invasion of Afghanistan in response to the Sept. 11, 2001 attacks. Some U.S. troops currently serving there had not yet been born when al-Qaida hijackers flew two airliners into the twin towers of the World Trade Center, crashed another into the Pentagon and took down a fourth in western Pennsylvania, killing almost 3,000 people.

It only took a few months to topple the Taliban and send Osama bin Laden and top al-Qaida militants scrambling across the border into Pakistan, but the war dragged on for years as the U.S. tried establish a stable, functioning state in one of the least developed countries in the world. The Taliban regrouped, and currently hold sway over half the country.

The U.S. spent more than $750 billion, and on all sides the war cost tens of thousands of lives lost, permanently scarred and indelibly interrupted. But the conflict was also frequently ignored by U.S. politicians and the American public as the memory of the attacks on that crisp, sunny morning faded despite having changed how many Americans see the world.

While Pompeo attended the ceremony in Qatar, where the Taliban have a political office, he did not sign the agreement and appeared to avoid any direct contact with the Taliban delegation. Instead, the deal was signed by U.S. peace envoy Zalmay Khalilzad and Taliban leader Mullah Abdul Ghani Baradar, after which they shook hands and members of the Taliban shouted “Allahu Akhbar” or “God is greatest.” Others in attendance, including the Qatari hosts, applauded politely.

“We are committed to implementing this agreement,” Baradar said in brief comments. “I call on all Afghans to honestly work for peace and gather around the table for peace negotiations.” He added that hoped the withdrawal of all foreign troops from Afghanistan would allow all Afghans to “have a peaceful life under Islamic law.”

Addressing reporters after the signing ceremony, Pompeo said he was still moved by the Sept. 11 attacks and proud of what the U.S. had accomplished in Afghanistan although he stressed that the U.S. must be realistic about its options.

“I am just as angry over 9/11 as I was the day I watched al-Qaida knock down the Twin Towers on TV,” Pompeo said before addressing U.S. veterans of Afghanistan and troops currently serving there. “We will not squander what they and you have won through blood sweat and tears,” he said.

Meanwhile in Kabul, in a rare show of unity, Ghani sat beside his political rival Abdullah Abdullah at a ceremony with Esper and NATO Secretary-General Jens Stoltenberg that included a declaration between the Afghan government and the United States intended to show U.S. support for Afghanistan as Washington signed the deal with the Taliban.

The declaration mirrored the Doha document in many ways, laying out the details of the U.S. agreement with the Taliban but conditional on its promise to battle terrorism. But for Afghanistan’s government which has been deeply criticized by its political opponents, including Abdullah, the real job ahead will be cobbling together a negotiating team to sit across from the Taliban in intra-Afghan negotiations to decide the future face of a post-war Afghanistan.

Those negotiations, to be held in Oslo, Norway, are expected to begin by March 10. But the Taliban want 5,000 of their prisoners released before the start of talks and until now Ghani’s government has not agreed. “After the signing between the United States and Taliban we will all work towards its implementation,” Ghani said. He took a conciliatory tone promising the negotiating team from Kabul will be “inclusive”, without giving detail.

Esper warned the road ahead was a long one and would not be without its challenges. “This is a hopeful moment, but it is only the beginning, the road ahead will not be easy. Achieving lasting peace in Afghanistan will require patience and compromise among all parties. But for the first time in many years, Afghanistan has a real path toward the future.”

Dozens of Taliban members had earlier held a small victory march in Qatar in which they waved the militant group’s white flags, according to a video shared on Taliban websites. “Today is the day of victory, which has come with the help of Allah,” said Abbas Stanikzai, one of the Taliban’s lead negotiators, who joined the march.

Trump has repeatedly promised to get the U.S. out of its “endless wars” in the Middle East, and the withdrawal of troops could provide a boost as he seeks re-election in a nation weary of involvement in distant conflicts.

He has approached the Taliban agreement cautiously, steering clear of the crowing surrounding other major foreign policy actions, such as his talks with North Korea.

Last September, on short notice, he called off what was to be a signing ceremony with the Taliban at Camp David after a series of new Taliban attacks. But he has since been supportive of the talks led by his special envoy, Zalmay Khalilzad.

Under the agreement, the Taliban promise not to let extremists use the country as a staging ground for attacking the U.S. or its allies. But U.S. officials are loath to trust the Taliban to fulfill their obligations.

The prospects for Afghanistan’s future are uncertain. The agreement sets the stage for peace talks involving Afghan factions, which are likely to be complicated. Under the agreement, 5,000 Taliban are to be released from Afghan-run jails, but it’s not known if the Afghan government will do that. There are also questions about whether militias loyal to various warlords will be willing to disarm.

U.S. officials say the eventual withdrawal of all American and allied troops from Afghanistan is not contingent on any specific outcome in talks among the Taliban and other Afghan factions about the country’s future. The officials spoke on condition of anonymity because they were not authorized to speak publicly about the agreement.

It’s not clear what will become of gains made in women’s rights since the toppling of the Taliban, which had repressed women and girls under a strict brand of Sharia law. Women’s rights in Afghanistan had been a top concern of both the Bush and Obama administration, but it remains a deeply conservative country, with women still struggling for basic rights.

There are currently more than 16,500 soldiers serving under the NATO banner, of which 8,000 are American. Germany has the next largest contingent, with 1,300 troops, followed by Britain with 1,100.

In all, 38 NATO countries are contributing forces to Afghanistan. The alliance officially concluded its combat mission in 2014 and now provides training and support to Afghan forces.

“The road to peace will be long and hard and there will be setbacks, and there is a risk always for spoilers,” Stoltenberg said on Saturday. “But the thing is, we are committed, the Afghan people are committed to peace, and we will continue to provide support.”

The U.S. has a separate contingent of 5,000 troops deployed to carry out counter-terrorism missions and provide air and ground support to Afghan forces when requested.

Since the start of negotiations with the Taliban, the U.S. has stepped up its air assaults on the Taliban as well as a local Islamic State affiliate. Last year the U.S. air force dropped more bombs on Afghanistan than in any year since 2013.

Seven days ago, the Taliban began a seven-day “reduction of violence” period, a prerequisite to the peace deal signing.

“The road to peace will be long and hard and there will be setbacks, and there is a risk always for spoilers,” Stoltenberg said. “But the thing is, we are committed, the Afghan people are committed to peace, and we will continue to provide support.”