In his first congressional testimony on the tumultuous withdrawal from Afghanistan, the top U.S. military officer has called the 20-year war a "strategic failure."
Gen. Mark Milley, chairman of the Joint Chiefs of Staff, also says he believes the U.S. should have kept several thousand troops in the country to prevent a Taliban takeover.
Milley said Tuesday he believes the U.S. should have kept at least 2,500 troops there to prevent a rapid Taliban victory, and he cited "a very real possibility" that al-Qaida or the Islamic State group's Afghanistan affiliate could reconstitute in Afghanistan under Taliban rule.
He added that setting a date for withdrawal was a poor strategy from the outset.
"As a matter of professional advice, I would advise and leader, don't put 'date certain' on end dates. Make things conditions-based," Milley said. "Two Presidents in a row put dates on it. My advice: Don't put specific dates. Make things specific based. That's how I've been trained over many, many years."
Milley said that after the Taliban seized control of the country, the U.S. military faced an uphill climb.
"If we had stayed past the [August] 31st, which was militarily feasible, it would have required an additional commitment of significant amount of forces, 15,000, 20,000, maybe 25,000 troops," Milley said. "We would have had to reseize, clear Kabul of the 6,000 Taliban that were already in Kabul. That's what would have happened on the beginning of the 1st [of September], and that would have resulted in significant casualties on the U.S. side and would have placed American citizens, that are still there, at greater risk."
Tuesday's hearing was the first public testimony on Afghanistan since the U.S. completed its pullout on Aug. 30.
Republicans in Congress have intensified their attacks on President Joe Biden's decision to pull all troops out of Afghanistan, saying it leaves the United States more vulnerable to terrorism. They are demanding more details on the suicide bombing in Kabul that killed 13 American service members.
In April, Biden announced that the U.S. would not be able to meet a May deadline for withdrawal from Afghanistan that the Trump administration had set. Instead, Biden delayed withdrawal until Aug. 31.
However, in the weeks leading up to the deadline, Taliban forces surged ahead and seized control of the country. With the oppressive regime in charge, thousands of Afghans and U.S. citizens sought refuge and attempted to leave the country through the Kabul airport.
The crowd surrounding the airport proved to be a soft target for ISIS terrorists, and a suicide bomber killed 13 American servicemembers and dozens of civilians on Aug. 26.
Tuesday's hearing will feature testimony from Sec. of Defense Lloyd Austin, Joint Chiefs of Staff chairman Gen. Mark Milley, and Gen. Kenneth McKenzie, the commander of the U.S. Central Command.