Editor’s Note: Retired Lt. Col. Jason Amerine is a 1993 graduate of the United States Military Academy with a bachelor of science in Arabic. He commanded a Special Forces team in Afghanistan after the terror attacks of September 11, 2001. Every member of the team was awarded the Purple Heart for combat wounds. The opinions expressed in this commentary are his own. View more opinion at CNN.

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As I communicated with the terrified families of former allies trying to flee the country this week, I felt the sickening resignation one has when visiting a loved one in hospice. But Afghanistan’s collapse was not pre-ordained. It was willful abandonment.

Jason Amerine

The arguments we’re hearing from officials about the inevitability of this collapse seem self-serving. The notion of inevitability removes blame or accountability.

The War on Terror began as the US response to the terror attacks of September 11, 2001, when al Qaeda hijackers, directed by Osama bin Laden in Taliban-controlled Afghanistan, took control of four US passenger jets and attacked the World Trade Center in New York and the Pentagon.

It coincided with a stalemate in Afghanistan’s civil war between Taliban forces and the warlord armies of the Northern Alliance. Following 9/11, the US plan was to support those armies in conquering the Taliban and seizing Kabul. The problem with the strategy was that sending these Northern Alliance forces composed of Uzbek, Tajik and Hazara fighters into the Pashtun tribal belt threatened to prolong the civil war rather than end it.

So the warlords of the Northern Alliance seized their tribal lands in the north while Hamid Karzai, a prominent member of the Pashtun tribe, sought to conquer the Pashtun territory in the south. My Special Forces team, along with a CIA paramilitary team, infiltrated Uruzgan province with Karzai to meet up with just a few dozen tribal fighters. Our unlikely campaign followed the same template we witnessed this week as the Taliban swept the country with lightning speed to topple Kabul.

From the start of our campaign, Karzai spoke to Mullah Abdul Ghani Baradar, a senior Taliban leader, almost daily. The conversations danced around the topic of surrender as the Northern Alliance quickly seized key cities in the North while Karzai secured the defections of Taliban-aligned tribes in the south.

Karzai’s narrative was simple: His forces had the military support of the US but he wanted the Pashtun to surrender peacefully. In the wake of 9/11, Pakistan was forced to suspend its support to the Taliban so their regime was isolated and crumbling. Baradar sent one of his last, large forces to attack Karzai’s small band of anti-Taliban fighters at Tarin Kowt. When they were routed by American air power, all the major Pashtun tribal leaders began defecting to Karzai’s side or declaring neutrality and ending support to the Taliban. Baradar surrendered Kandahar and Afghanistan itself to Karzai in early December 2001.

Amerine and his Special Forces teammates with future Afghan President Hamid Karzai in Afghanistan on December 3, 2001.

With the fall of the Taliban, the US and coalition forces demobilized all the warlords’ armies and established the Afghan National Army in hopes of empowering Kabul. Afghanistan was to be protected by an ethnically integrated army controlled by the central government. And the Taliban leadership, who fled to Pakistan, regrouped as Pakistan quietly supported this growing threat (Pakistan has long denied supporting the Taliban).

The invasion of Iraq caused the entire US military to be drawn into a bloody insurgency that pushed the limits of our all-volunteer army to sustain itself. In Afghanistan, the demobilization of the warlord armies created a security vacuum that slowly spawned a Taliban insurgency, supported by Pakistan.

The Afghan National Army was still in its infancy and the US could not send forces to respond to this threat as it fought to prevent the collapse of Iraq. The US could not even sanction Pakistan for supporting the Taliban because all of the major supply lines supporting US forces went through Pakistan and had to be maintained through polite diplomacy.

Years of benign neglect followed in Afghanistan as Kabul and all our Afghan allies became more and more alienated by America’s lack of action to combat the Taliban. Kabul’s legitimacy was based on the Loya Jirga, a tribal council that established the government. But the defense of the nation rested on the Afghan National Army that could only stand and fight when supported by coalition partners. And Kabul faced an insurgency supported by Pakistan.

The question was: whose support would endure? America’s support of Kabul or Pakistan’s support to the Taliban? Few believed the US would stay indefinitely and the Afghan National Army needed generations to become a viable fighting force as Afghanistan faced a growing insurgency that had become another civil war.

For all the criticism of the Afghan National Army’s lack of capability, many Americans forget our own Civil War. Though the Federal Army fought the Confederate Army, both armies were composed of locally raised forces like Joshua Chamberlain’s famed 20th Maine Volunteer Infantry Regiment that was made famous for defeating the 15th Alabama Infantry Regiment at Gettysburg. Such forces fought bloody battles across America that eventually led to the standing army we have today with no such regional affiliations. But that took decades.

But in Afghanistan, locally raised and highly cohesive insurgent tribal forces supported by Pakistan fought a fledgling Afghan National Army that was simply outmatched without coalition forces fighting at its side. Afghanistan settled into a stalemate as Kabul retained control of what territory it could and the Taliban avoided direct confrontations with coalition forces that it could not defeat. The years ticked on as the US effort was simply aimed at maintaining this status quo and depended on an Afghan Army that could not stand without us.

Amerine with Karzai and former Afghan President Burhanuddin Rabbani in 2004.

With the election of President Barack Obama, the US announced a plan to withdraw from Afghanistan and the people of Afghanistan faced a stark choice: believe in Kabul, backed by an incapable Army that would soon have to stand on its own, or accept that the Taliban were likely going to seize control once again with the backing of Pakistan.

The Taliban began carrying out the same negotiations with the Pashtun tribes that Hamid Karzai carried out in 2001. Their message was simple: the US will abandon Kabul while the Taliban have the backing of Pakistan. With no significant warlord armies left to counter their widening grip on the country due to their demobilization, tribes all across Afghanistan began negotiating for their capitulation once the US departed.

The Obama administration quickly recognized how precarious the situation was in Afghanistan and indefinitely delayed such a withdrawal. If nothing else, it did not want to be the author of Kabul’s collapse. But the election of President Donald Trump led to his repeated calls for an immediate withdrawal that established a framework for US departure.

Many believed President Joe Biden would be more cautious once elected. He witnessed the disastrous fragmentation of Iraq and rise of ISIS when the US departed precipitously. But he pressed on anyway, executing the withdrawal of US forces that left the tribes of Afghanistan little choice but capitulation. The ANA collapsed predictably and there was no longer a Northern Alliance to rally behind. And so everyone surrendered as quickly in 2021 as they did in 2001. The circle was complete.

Rumor has it that Karzai again negotiated with Baradar in the final days of the Afghan government this week: the roles were reversed as Karzai again sought to limit bloodshed. I do not know if this is true. But the unfolding humanitarian disaster will be anything but bloodless.

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    Our mission in 2001 was to remove the terrorist safe havens of Afghanistan. It was an act of revenge. I was proud to see it evolve into something more as little girls went to school and women were allowed to vote. But now the noblest gains of our mission are lost and we are left to say, “At least we got Bin Laden.” It just rings so hollow to me.

    The last text from a man I fought beside at Tarin Kowt reads “Hi, Jason my dear friend, thank you for your support…Taliban is already here, if I survive we will contact again. Thank you for everything.”

    I will never understand why he thanked me.

    This article was updated from an earlier version, which misstated the date the war on terror began. It was September 11, 2001.