On Sept. 11, 2001, I was a CIA chief of station working abroad and handling a sensitive infiltration of al-Qaeda, what the Clandestine Service refers to as a “penetration.” As he would later realize, my agent was familiar with several of the hijackers and their associates. At the time, he sensed something evil was coming, but was too removed from any insight into the planning of the attack to warn us. He would prove valuable in identifying what al-Qaeda might do next, and those who could carry it out, but I have never lost the nagging sense of guilt at what I might have done differently to translate his dread and broader insights into more compelling action. As the United States moves toward an accelerated departure from Afghanistan, that nagging feeling is growing louder, amplified as we mark the 19th anniversary of 9/11.

Like so many, I mourn the 2,997 souls who perished in New York City, at the Pentagon, and in Pennsylvania. Among those killed was a first responder and childhood friend of mine. I also grieve for the 7,052 American service members who died and the 53,244 wounded in the wars launched in the aftermath of 9/11. I mourn the hundreds of thousands killed, wounded, and displaced across Afghanistan, Iraq, Syria, Yemen, and elsewhere, having witnessed the carnage first-hand and looked into the eyes of some of those responsible. And like many in America who are old enough to remember, I mourn the blissfully ignorant sense of security we enjoyed before the planes hit the Twin Towers.

Now, almost 20 years later, Americans understandably want out of Afghanistan, the “forever war,” which now seems so distant, and to many, a worthless drain on our precious blood and treasure. But just as a false sense of security pervaded the country before 9/11, the threats still hiding in Afghanistan will not disappear by believing them gone and proclaiming “game over.” Repeating the same mistakes in Afghanistan of the last 19 years is not the answer, but neither is closing our eyes and packing up to go home for the wrong reasons and under these circumstances.

Against the backdrop of polls reflecting former Vice President Joe Biden’s growing electoral college lead, President Donald Trump made a surprising declaration during an August 3 interview with Axios on HBO to reduce the number of U.S. troops in Afghanistan from 8,600 to as few as 4,000 as soon as November. Defense Secretary Mark Esper rather meekly confirmed the news after Trump made it public. Similarly, Trump announced this week that troop levels in Iraq would also be brought down before the U.S. election, with no indication the withdrawal is tied to conditions on the ground. These moves are part of a series of announcements and last-minute “victories” being orchestrated by the Trump administration in the lead up to November’s election, including unfounded boasts of bringing peace to the Middle East and promising a COVID-19 vaccine in the coming months.

In Afghanistan, unilaterally accelerating the U.S. withdrawal ahead of the timeline included in the February 29, 2020 agreement negotiated with the Taliban offers no strategic benefit. It undercuts U.S. leverage and validates the Taliban’s unwillingness to meet America’s most critical goal of severing ties to al-Qaeda and its partner organizations, a condition it has failed to meet, according to General Frank McKenzie, head of U.S. Central Command. Moreover, doing so undermines U.S. and ultimately Afghan negotiators’ efforts to incentivize the Taliban into a negotiated peace process rather than its evident, ongoing pursuit of outright military victory.

Whoever sits in the White House on January 21, 2021 will inherit a credible and ongoing terrorist threat from al-Qaeda and its partner groups across the Afghanistan/Pakistan region. The severity and urgency will be contingent upon the U.S. military footprint and the status of political reconciliation among the groups vying for power and control. It will likewise be influenced by great power competition with Russia and China, the enduring Pakistan-India conflict, and tensions with Iran. The region being home of the historically un-winnable “Great Game,” players nonetheless accept the cost to protect a greater prize. For the U.S., what’s at stake is the insight and leverage needed to protect the U.S. homeland from further attacks.

Core al-Qaeda, its local affiliate al-Qaeda in the Indian Subcontinent (AQIS), the local Islamic State branch, the Islamic State in the Khorasan Province (ISKP), and several designated terrorist groups which partner with al-Qaeda, continue to aspire to strike U.S. interests across the region, as well as the U.S. homeland. While not a household name in the United States, Tehrik-e Taliban Pakistan just missed in its failed May 2010 vehicle-bomb attack in Times Square after successfully executing the 2009 suicide bombing at U.S. Forward Operating Base Chapman that killed 9 CIA officers in Afghanistan. Lashkar-e-Tayyiba, which carried out the deadly 2008 Mumbai attack, employed American citizen David Coleman Headley, and has increasingly embraced a more global jihadist mission. And these two groups are but a few of the roughly dozen or so other organizations closely collaborating with al-Qaeda and the Taliban that show no sign of abandoning their quest to strike the United States.

Al-Qaeda and its partner groups operate with varying degrees of capability and have been to date constrained from developing complex operations beyond the region due to sustained U.S. counterterrorism pressure. The intelligence collection lost from the U.S. leaving Afghanistan will fall well short of what is needed to identify evolving threats. Nor will it be sufficiently robust or timely to provide the granular details required to support direct action from military capabilities, such as targeted killing operations that take out terrorist leaders, that will now need to be relocated beyond Afghanistan’s borders.

The intelligence required to save American lives at home and abroad depends on the U.S. military footprint, infrastructure, and enablers to let collectors operate and special missions proceed. I oversaw CIA’s counterterrorism activities in the region and can tell you, the nature of the environment, its culture, and operational conditions requires meeting agents regularly, and in person. Agents, most of whom have neither the means nor excuse, can’t simply hop on a plane and leave the country to meet their case officer. Other options exist, but are limited in effectiveness by the very same considerations.

Granted, there is a low probability any of these groups could in the immediate term successfully plan, manage and execute an attack against the U.S. homeland on a scale comparable to 9/11. But all have demonstrated the capacity to inspire and guide lone wolves in the U.S. and across the globe. In the interim, al-Qaeda and its partner groups will be able to reconstitute as counterterrorism pressure recedes. A conservative estimate of the time required for al-Qaeda to reconstitute sufficient capability to attack the U.S. is informed by the Islamic State’s ability in 2015 to execute centrally driven attacks in Europe following the 2013-2014 establishment of its caliphate across Syria and Iraq, and varies from one to two years. But that presumes al-Qaeda has not already made strides since U.S. pressure has receded, as I suspect to be the case.

Al-Qaeda’s resiliency can largely be attributed to ongoing Taliban protection in Afghanistan and the ability of senior, Iran-based al-Qaeda leaders to manage worldwide activities. Affiliates, such as al-Qaeda in the Arabian Peninsula in Yemen and Hurras al-Din in Syria, have carried out innovative efforts aimed at striking civilian airliners and soft targets in the West and remain compliant with al-Qaeda Amir Ayman Zawahiri’s centralized command.

Still believed to be somewhere in Afghanistan, Zawahiri continues to manage worldwide activities by the sanctuary the Taliban offers. Plus his lines of communication through  lieutenants like Egyptian nationals Saif al-Adil and Abu Muhammad al-Masri must be improving as the U.S. presence recedes and Taliban territorial gains expand.

Gazing at Tora Bora’s mountains, the streams of the Panjshir Valley, and the wall around Kabul’s old city, always made me reflect on Afghanistan’s innate beauty, as well as its violent past in bleeding empires. One is likely to lose if seeking to change Afghanistan into something it’s not, as has largely been the post-9/11 strategy. But this doesn’t mean the United States can ignore the threats that still persist there and will soon be free to strike out. The next administration will need to see Afghanistan clearly for what it is and understand where threats might come from in order to achieve a better informed and more realistic balance that’s required to achieve the desired results. No such enlightenment will be forthcoming if we simply close our eyes and pretend it is what we wish or need it to be.

Image: U.S. soldiers with an artillery supply infantry unit patrol April 24, 2004 in Morgan Keckeh, Afghanistan. Photo by Yoray Liberman/Getty Images