(WASHINGTON) -- The top two military leaders who oversaw the U.S. withdrawal from Afghanistan in 2021 testified Tuesday afternoon before the House Foreign Affairs Committee in a hearing meant to assess the Biden administration's role in the chaos that unfolded at the end of America's longest war.
One of those leaders was Gen. Mark Milley, who retired as chairman of the Joint Chiefs of Staff last September. He was set to face tough questions from Republican lawmakers on the panel -- reflecting how the withdrawal has become a persistent part of conservative criticism of the White House.
Milley told ABC News' Martha Raddatz in a 2023 interview that he had "lots of regrets" about how the 20-year conflict concluded.
"In the broader sense, the war was lost," he said then.
Milley expressed a similar sentiment in his opening remarks Tuesday.
"At the end of 20 years, we the military helped build an army, a state, but we could not forge a nation. The enemy occupied Kabul, the overthrow of the government occurred and the military we supported for two decades faded away. That is a strategic failure," Milley said.
He added that despite that wider failure, some good was done.
"The military also provided hope for 20 years to the Afghan people -- we provided unprecedented opportunity to millions," he said.
In August 2021, the U.S. military and State Department scrambled to evacuate some 124,000 embassy personnel, Americans and at-risk Afghans following the Taliban's swift march to the capital of Kabul, facing relatively little opposition on the way from Afghan forces or the national government, which swiftly collapsed as well.
The evacuation efforts were centered on Hamid Karzai International Airport in Kabul.
On Aug. 26, an ISIS-K terrorist detonated a suicide bomb at the Abbey Gate of the airport, killing 13 U.S. service members and at least 170 Afghans.
Gold Star families of several of the U.S. service members killed in that attack were present for Tuesday's hearing.
"I'm humbled to be here today with three Gold Star families from Abbey Gate, and I know the other families couldn't make it, but I intend to contact them in the coming weeks," Milley said in his opening remarks before the committee. "They know that there are no words by me or any general or any politician or anyone that can ever bring back their fallen."
Asked if lack of prudent planning contributed to the chaos at the airport amid the evacuation efforts, Milley said before the committee that the decision to execute a noncombatant evacuation operation (NEO), which initiates the departure of civilians and nonessential troops, "came too late."
Gen. Kenneth "Frank" McKenzie, who was the top U.S. general in the Middle East during the withdrawal, also testified beside Milley on Tuesday.
He echoed Milley's comments on what he conceded was a late call to evacuate, placing blame on the State Department, which holds the authority to initiate such operations.
"I believe that the events of mid and late August 2021 were the direct result of delaying the initiation of the NEO for several months," McKenzie said. "In fact, until we were in extremists, and the Taliban had overrun the country -- as you are aware of, the decision to begin a NEO rests with the Department of State, not the Department of Defense. Despite this, we had begun positioning forces in the region as early as nine July, but we could do nothing."
Despite U.S. efforts, an unknown number of Americans and Afghans seeking to escape persecution by the Taliban were left behind, Milley said.
"I'll be candid, I don't know the exact number of Americans that were left behind, because the starting number was never clear," he said. "Same is true of at-risk Afghans, SIVs [referring to a special visa program], the commandos, other Afghans that served with us -- those numbers varied so widely that they were quite inaccurate."
These topics have been addressed on the Hill before. Milley and McKenzie told the Senate Armed Services Committee in 2021 that their recommendation to President Joe Biden earlier that year was to maintain a modest presence of some 2,500 troops in Afghanistan beyond Aug. 31, when the full withdrawal eventually ended.
Biden contradicted that during an Aug 18, 2021, interview with ABC News anchor George Stephanopoulos.
On Tuesday, McKenzie, who retired in 2022, reaffirmed that he effectively relayed his advice to the president: "I participated in meetings at the very highest level where I expressed the opinion I just stated to you, and it was heard," he said during an exchange on the matter.
While Republican congressmen continually hammered during the hearing at the discrepancy between the recollections of Biden and his former military leaders, Democrats have attempted to shift blame to the Trump administration, mainly for the controversial agreement the U.S. signed with the Taliban when Donald Trump was in office that laid the groundwork for the withdrawal.
Miley told the committee that had the U.S. not adhered to its promise to leave, "I think the probability is greater than not that the Taliban would have reinitiated combat operations."
Another point of contention pressed by GOP congressmen was over the previous testimony of Marine Sgt. Tyler Vargas-Andrews, who claims to have had a man matching a description of the Abbey Gate suicide bomber in his sights before the deadly explosion on Aug. 26, but Vargas-Andrews said he was not given permission to engage and prevent the blast.
Vargas-Andrews lost two limbs in the blast and was present at Tuesday's hearing.
McKenzie said he is not aware of any "BOLO" -- be on the lookout -- alert given to U.S. forces at the time matching the description given by Vargas-Andrews.
Rep. Mills accused McKenzie of calling the Marine's integrity into question, asking the retired general, "Do you want to face him and tell him that before him now?"
"I don't want to face him and tell him that. I want to say that the battlefield is a very complex place. There were a lot of threats that were floating around out there that day. I honor his service. I regret he was injured," McKenzie responded.
Milley said he would like to personally speak with Vargas-Andrews.
"Obviously, something broke down. If Sgt. Vargas had a positive ID on a known enemy target, that enemy target was hostile act or hostile intent, the rules of engagement allowed it," he said.