In the span of days, Taliban fighters have overrun a string of provincial capitals as part of a major offensive launched after American and international troops began to pull out of the country in May.
“All of the momentum is going one way right now," one U.S. defense official said.
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Yet, earlier this week President Joe Biden made clear he has no plans to change course as the U.S. aims to complete its withdrawal from Afghanistan by September 11, the 20th anniversary of the 9/11 terror attacks.
"Afghan leaders have to come together,” Biden told reporters at the White House on Tuesday. “They have got to fight for themselves, fight for their nation.”
The Afghan government deployed Special Operators to Kandahar City, Lashkar Gah, Mazar-i-sharif, and Herat City in recent weeks to shore the key areas up against relentless Taliban attacks, the three officials said, but now many of the elite Afghan forces are stretched thin and weary after weeks of fighting.
Meanwhile, the U.S. military is still conducting one to five airstrikes each day — weather permitting — a defense official said, primarily using unmanned drones that are flown from neighboring countries.
The U.S. military is authorized to support the Afghan military with airstrikes against the Taliban until the end of this month, and does not expect the mission to be extended, according to defense officials.
After withdrawing nearly every U.S. military asset from Afghanistan, the U.S. deployed a small number of helicopters, pilots and maintainers back to Kabul so the U.S. could also fly manned airstrike missions, too. The helicopters are to provide personnel recovery in case one of the manned fighter jets goes down.
Most of the U.S. airstrikes destroy equipment that the Taliban have stolen from the Afghan military and police as they take over territory, including some weapons and equipment supplied by the U.S.
In recent weeks, U.S. airstrikes have destroyed multiple D30 artillery pieces, multiple tanks, MRAPs and Humvees that the Taliban could use to target Afghan Security Forces.
While these strikes can have a tactical or immediate impact on a specific battle, the airstrikes on a whole are not having a strategic impact on the fight between the Afghan military and the Taliban, the U.S. defense official said.
A handful of U.S. airstrikes will not stop the Taliban, they said.
The warning comes as the Taliban makes gains in the pivotal province of Kandahar, with the militant group announcing it had overrun the Kandahar Central Jail, or Sarposa Prison, and released hundreds of inmates on Wednesday.
"Hundreds of prisoners were released and taken to safety," he said.
NBC News was unable to verify the claims, but targeting jails and prisons has long been a key component of the Taliban's military strategy. Militants free the prisoners with the intention of enlisting them in the group's fight.
In Ghazni, a strategic provincial capital on the road to Kabul, the province's governor was arrested by security forces on Thursday, according to the country's interior ministry.
That came as the Taliban captured most of the city, according to the Associated Press, potentially cutting off a crucial highway linking the Afghan capital with the country’s southern provinces.