The U.S. administration of President Joe Biden said Monday it has completed the withdrawal of its troops from Afghanistan, bringing an end to two decades of war triggered by the terror attacks of Sept. 11, 2001, on American soil.

While the troop removal itself has been widely supported by the public, the cost of the U.S. pullout has been high as the move made way for the Taliban's return to power for the first time in about 20 years and resulted in chaotic and deadly evacuation efforts for Americans and Afghans who worked alongside the United States.

"Now, our 20-year military presence in Afghanistan has ended," Biden said in a statement, referring to the withdrawal that came just ahead of his self-imposed deadline on Tuesday.

The U.S. military said the last C-17 aircraft lifted off from the international airport in Kabul at 11:59 p.m. local time. A Taliban spokesman declared "complete independence," saying that the last U.S. soldier has left Kabul airport, according to Al Jazeera TV.

Biden said he will address the nation on his decision to end the U.S. military presence in Afghanistan on Tuesday, while pledging that the United States will continue to lead coordination with other countries to ensure safe passage for any Americans, Afghans or foreign nationals who want to get out of the war-torn country.

The U.S. retreat from Afghanistan, meanwhile, leaves concerns over the possibility of Afghanistan becoming once again a safe haven for terrorists as well as the potential for severe erosion of civil liberties under the rule of the Taliban, known for oppressing women during its former rule.

The Biden administration has taken the position that ending the longest U.S. war in history will help it focus on current threats and challenges posed by increasing competition with China as well as a distributed terrorist threat across multiple countries.

But what was perceived by many as a botched Afghanistan exit and the U.S. intention to engage only where national interests are at stake have led China to step up its anti-U.S. rhetoric and raised questions about the strength of U.S. security commitments with allies in Asia in particular.

The United States began the war in Afghanistan in response to the Sept. 11 terror attacks by the al-Qaida organization, which was being harbored by the Taliban, a militant Islamist group.

 

The Taliban regime was toppled by U.S.-led forces by the end of 2001 and al-Qaida leader Osama bin Laden, the mastermind behind the terror attacks, was killed in 2011. But the U.S. and Afghan governments, along with other partner countries, remained in combat with Taliban insurgents.

Reflecting the U.S. public's wariness of continuing "endless wars," the previous administration under Donald Trump committed to withdrawing the country's military forces by May 1, 2021. The Biden administration moved the deadline to the end of August, just before the 20th anniversary of the terror attacks.

But what Biden promised would be an "orderly and safe" drawdown of U.S. personnel and evacuation of Afghan partners has apparently been marred by miscalculations.

After the Taliban took control of the capital on Aug. 15 and President Ashraf Ghani fled the country, thousands of Afghans rushed to Kabul airport, with some falling from deadly heights after trying to cling to the outside of a departing U.S. military plane in a desperate attempt to flee Taliban rule.

Biden has insisted that his administration had planned for "every contingency," but admitted that "the truth is this did unfold more quickly than we had anticipated."

Tensions grew toward the end of the troop withdrawal as an Islamic State suicide bombing near the airport on Thursday killed many Afghans and 13 U.S. service members, reportedly becoming the deadliest incident for U.S. troops in Afghanistan in a decade.

According to the U.S. Defense Department, 2,461 service members were killed in the war, including those who died in Thursday's attack by the extremist group.

U.S. Secretary of State Antony Blinken sought to highlight the achievements of the last few weeks -- which saw a number of countries including Japan send planes for the evacuation -- saying more than 123,000 people have been safely flown out of Afghanistan, including about 6,000 American citizens, "under some of the most challenging circumstances imaginable."

But he acknowledged there are still up to 200 Americans who remain in Afghanistan and want to leave.

Blinken said he virtually met with the foreign ministers of the Group of Seven industrialized nations, which includes Japan, as well as Qatar, Turkey and others earlier Monday to discuss how they can work together to facilitate further safe travel out of Afghanistan.

He also said that if the Taliban seeks any international legitimacy and support, it must meet commitments and obligations on freedom of travel, respecting the basic rights of the Afghan people, including women and minorities and upholding its commitments on counterterrorism, among other issues.

The United States, for its part, will maintain "robust counterterrorism capabilities in the region" to neutralize threats, even without the military presence in Afghanistan, Blinken said.

As of Monday, the United States has suspended its diplomatic presence in Kabul and transferred its operations to the Qatari capital of Doha.