Politico describes how the Biden administration responded:
By the morning of Wednesday, Aug. 11, the Afghan government’s already brittle control of the war-torn country was quickly unraveling in the face of a swift Taliban offensive coinciding with the nearly complete withdrawal of U.S. troops that President JOE BIDEN ordered in April.
Most of America’s top diplomats and generals were still operating under the assumption that they had ample time to prepare for a Taliban takeover of the country — it might even be a couple of years until the group was in a position to regain power, many thought. Though some military officials and intelligence agencies had stepped up their warnings about the possibility of a government collapse, officials felt confident about the Afghan security forces’ strategy of consolidating in the cities to defend the urban population centers.
The president and his top aides still had one more meeting scheduled for Wednesday evening — a pre-planned session on a classified national security matter. As word of the deteriorating situation flowed into the Oval Office that morning, Biden ordered that the early evening meeting should focus on Afghanistan.
Sitting in the Situation Room were [the Vice President, Secretary of Defense, chairman of the Joint Chiefs of Staff; the National Security Adviser; the Director of National Intelligence; the Deputy CIA Director and others. Other officials, including the Secretary of State, participated by phone].
Events were growing so dire that the president ordered [Sec. of Defense] Austin and [General] Milley to prepare a plan for deploying additional troops to the region, where they would reinforce those put on standby months earlier to evacuate American personnel.
Biden also directed the State Department to expand the evacuation of Afghan allies — those who had worked with the Americans and were now in mortal danger — to include the use of military aircraft, not just chartered civilian planes.
And he also asked his intelligence officials to prepare an up-to-date assessment on the situation in Afghanistan by the following morning. After the meeting broke up, a classified email was sent to pertinent staffers to convene at 7:30 a.m. the next day [August 12].
. . . The principals meeting kicked off with an intelligence briefing concluding that the situation was so “fluid” that the Afghan government’s seat of power in Kabul could fall “within weeks or days,” an official noted.
Austin recommended that Biden send in troops to evacuate the embassy and protect the main international airport in Kabul. [National Security Adviser] Jake Sullivan asked each Cabinet member in the meeting to weigh in. They unanimously agreed.
That was the “Oh, shit” moment, said a U.S. official. It was now officially a crisis.
Sullivan walked into the Oval Office just before 10 a.m. [on August 12] to report to the president. Biden picked up the phone and told Austin to send troops to Kabul’s airport.
Some background from The Hill:
History will mark Aug. 15, 2021, as the date that the Afghan government collapsed and the Taliban retook control over this troubled and war-torn country. But the real date that the Taliban’s victory was assured is Feb. 29, 2020, the day the T____ administration signed what it characterized as a “peace” deal with the Taliban. Once this agreement was signed — the tragic collapse we witnessed this weekend was inevitable.
Of course, the agreement was not, and could not possibly have been, a “peace” deal since one of the parties currently at war — the Afghan government — was not a signatory. Rather, this was a “withdrawal” agreement between the U.S. and the Taliban that set the terms for the complete departure of American troops from Afghanistan by May 2021.
What did the United States gain in exchange for this withdrawal, for which the Taliban had been fighting for 20 years? Nothing but vague, unenforceable promises that the Taliban would not engage in hostilities against the departing U.S. troops and would “send a clear message” to al Qaeda that it “had no place” in Afghanistan. So eager T____ was to withdraw, we did not even hold out for a clear, firm commitment that the Taliban would not provide aid, safe harbor or weaponry to al Qaeda and like-minded groups. The agreement contained no enforcement mechanisms and included no penalties on the Taliban for failing to comply with its terms.
Once the agreement was signed, the fate of the Afghan government was signed, sealed and delivered — the Taliban had practically won the war. There was no way that the government could possibly survive.
The fact that the United States entered into negotiations and then an agreement with the Taliban, without even inviting the Afghan government to the table, undercut the power and legitimacy of the government. The citizenry, including those in the national armed services and police, could plainly see that its own government was being ignored, a helpless bystander in critical discussions about the country’s future. After we had cut the legs out from under this government and rendered it a paper tiger, it is no wonder that when those serving in the Afghan army and police were asked to fight, most said, “No, thanks.”
The agreement also did absolutely nothing to attempt to bring about a peaceful settlement of the war between the Afghan government and the Taliban. A genuine peace deal would have made our withdrawal contingent on the progress of peace negotiations between the Afghan government and the Taliban. But it did not. T____ agreed unconditionally to bring down U.S. troop levels to 8,600 by mid-July 2020 and totally withdraw by May 2021.
The agreement anticipated there would be peace negotiations, but in August, T____ voluntarily cut troop levels down to 4,500, even more quickly than required by the agreement, even though negotiations had not even begun. This was a clear signal there would be no linkage between withdrawals and peace, contrary to what U.S. diplomats were telling the parties. This signal was received loud and clear by the Taliban. They balked at starting negotiations until December, and even then, had zero incentive to make any concessions since T____ had already announced that there would be only 2,500 troops in Afghanistan by the time he left office, the smallest U.S. force in 20 years. It was clear to the Taliban that the Americans were quickly headed for the exits. . . . .
To stem the Taliban’s momentum on the ground this spring, the Biden administration would have had to not only abrogate the T____ withdrawal agreement but also deploy more troops and get them more deeply involved in the fighting. This would have breached Biden’s campaign commitment to end the war in Afghanistan and ran against the strong bipartisan public support for withdrawal.
Paul Waldman of The Washington Post explains why discussion of these events in the media has been so distorted: