(WASHINGTON) — The top two military leaders who oversaw the U.S. withdrawal from Afghanistan in 2021 are testifying 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 the America’s longest war.

One of those leaders is Gen. Mark Milley, who retired as chairman of the Joint Chiefs of Staff last September. He is likely 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.

The second senior military leader testifying before the committee is Gen. Kenneth “Frank” McKenzie, who was the top U.S. general in the Middle East during the withdrawal from Afghanistan.

McKenzie has also expressed regrets — in particular over not having earlier evacuated embassy staff, U.S. citizens and Afghans seeking escape as the Taliban again took over the country.

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 from Afghan forces or its national government, which swiftly collapsed.

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 are 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.”

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