Taliban fighters take control of Afghan presidential palace after the Afghan President Ashraf Ghani fled the country, in Kabul, Afghanistan, Sunday, Aug. 15, 2021.Zabi Karimi | APWASHINGTON — The Taliban seized the presidential palace in the war-weary Afghan capital of Kabul on Sunday, a dramatic development that marks the apparent end to a 20-year American era in the country.The stunning revelation comes hours after Taliban insurgents pushed their frontlines into Kabul after a succession of shocking battlefield reversals, spurred by the exodus of U.S. and coalition forces.Earlier on Sunday, Afghan President Ashraf Ghani fled the country as Western nations rushed to evacuate embassies amid a deteriorating security situation.Secretary of State Antony Blinken, who appeared on several Sunday news programs, fell short of saying that the U.S. Embassy in Kabul would effectively be abandoned. He added that a “core diplomatic presence” will now be headquartered at the Hamid Karzai International Airport.The State Department said Sunday evening that all U.S. embassy personnel were safely evacuated by military helicopter from the embassy compound to the airport in Kabul.”All Embassy personnel are located on the premises of Hamid Karzai International Airport whose perimeter is secured by the U.S. military,” State Department spokesman Ned Price said.The latest revelation follows President Joe Biden’s order to deploy approximately 5,000 U.S. troops to Kabul to evacuate embassy staff. Meanwhile, the State Department instructed U.S. Embassy personnel on the ground to destroy sensitive information material ahead of their departure.Britain, Germany and Canada also rushed troops into Kabul to evacuate their embassies.In recent days, the Taliban made stunning battlefield reversals with now nearly the entirety of the nation under their control.Despite being vastly outnumbered by the Afghan military, which has long been assisted by U.S. and coalition forces, the Taliban entered Kabul on Sunday.Afghanistan’s President Ashraf Ghani attends a security meeting in Kabul, Afghanistan August 14, 2021.Afghan Presidential Palace | ReutersTwo U.S. defense officials confirmed to NBC News that the Taliban also seized Bagram Air Base, a development that comes less than two months after the U.S. military handed over the once-stalwart airbase to the Afghan National Security and Defense Force.The group began emptying out Parwan prison there which has an estimated 5,000 to 7,000 prisoners, including hardened Taliban and al Qaeda fighters, according to the officials, who spoke on the condition of anonymity.In 2012, at its peak, Bagram saw more than 100,000 U.S. troops pass through. It was the largest U.S. military installation in Afghanistan.Last week, the group captured Kandahar and Herat, Afghanistan’s second- and third-largest cities. The group also took the strategic town of Pul-e-Alam, a city that has one of the four main roads to Kabul.’They’ve got to fight for themselves’Taliban fighters sit over a vehicle on a street in Laghman province on August 15, 2021.AFP | Getty ImagesBiden told reporters last week at the White House that he did not regret his decision to withdraw U.S. forces from Afghanistan, effectively ending America’s longest war.”Look, we spent over a trillion dollars over 20 years, we trained and equipped with modern equipment over 300,000 Afghan forces,” Biden said on August 10.”Afghan leaders have to come together,” the president added. “They’ve got to fight for themselves, fight for their nation.”In April, Biden ordered the Pentagon to withdraw U.S. troops from Afghanistan by Sept. 11, a decision he said was made in lockstep with NATO coalition forces.CNBC PoliticsRead more of CNBC’s politics coverage:The Pentagon’s colossal task of removing servicemembers and equipment out of Afghanistan is nearly complete, with the U.S. military mission slated to end by Aug. 31.The Pentagon has previously said that the continued Taliban offensive across the country runs against a commitment made last year by the group to engage in peace talks with the Afghan government.The peace talks, which are hosted in Qatar, have since stalled.”What we’re seeing on the ground is that the Taliban continues to advance and to assume control of district and provincial centers that clearly indicates that they believe it is possible to gain governance through force, through brutality, through violence, through oppression, which is at great odds with their previously stated goal of actually wanting to participate in a negotiated political solution,” Pentagon spokesman John Kirby told reporters recently.He added that while the Pentagon is concerned to see such advances by the Taliban, the Afghan military must now leverage the nearly two decades of training from U.S. and NATO coalition forces.”They have the advantage in numbers, in operational structure, in air forces and in modern weaponry and it’s really about having the will and the leadership to use those advantages to their own benefit,” Kirby said.”The recipe can’t be just a constant U.S. presence in Afghanistan that never ends,” he added.