Editor's note:This is the fifth piece of the series "One Year: Taliban in, U.S. out."  Song Xin is a former political advisor at the European Parliament. The article reflects the author's opinions and not necessarily those of CGTN.

Exactly one year ago, the remaining U.S. military forces departed from Afghanistan, which ended the United States' longest war. The withdrawal endured two weeks of chaos while more than 120,000 people were evacuated. The day after that, U.S. President Joe Biden claimed that the U.S. should learn from its mistakes and the withdrawal marked the end of an era of major military operations to "remake" other countries. U.S. Secretary of State Antony Blinken said Washington would work more on diplomatic engagement with Kabul.

Washington and the Taliban signed a peace agreement in 2020, with the expectation that the Taliban would take part in peace negotiations with the Afghan government. Nonetheless, the U.S. had already started to withdraw its troops before the peace talks started. The Taliban felt emboldened by the rapid U.S. withdrawal and quickly took control of several provincial capitals and then the whole country within a few months. By mid-August 2021, the central government collapsed when the Taliban captured the capital city, Kabul.

The U.S. government had failed, since. Washington never anticipated how quickly the Taliban would surge back. Additionally, Washington didn't have a follow-up plan for the area. Apparently, the U.S. only wanted to flee from the muddy puddles as soon as possible, leading to the intertwined strategic and bureaucratic blunders.

President Biden took the responsibility by saying, "I am president of the U.S. and the buck stops with me." But Biden didn't want to take all the criticisms. He blamed Afghan political leaders for "giving up and flee the country." The Afghan military collapsed, sometimes without a fight. Apart from his former partners, he also threw Donald Trump under the bus by saying that the Doha Agreement that Trump had signed with the Taliban in 2020 led to the chaotic withdrawal.

"Probably the worst thing he said was when he basically balled it all on Trump," said Ryan Crocker, former U.S. ambassador who served twice in Afghanistan. In fact, U.S. citizens were also unsatisfied with the Biden' administration during and after the withdrawal. Ever since last August, his approval ratings have plunged and never recovered.

"If bringing competence back to government is one of the kind of hallmarks of a candidacy, then I think the optics of the Afghanistan withdrawal go completely against the sort of rationale of why you should have voted for Biden," said Dough Sosnik, a former advisor to President Bill Clinton.

The internal and independent reviews are ongoing. The Afghanistan War Commission, composed of 16 members, intends to pursue a three-plus-year study over what had gone wrong. The U.S. Department of Defense is reviewing its assessment and the U.S. Department of State is also conducting an after-action review. Besides, the Special Inspector General for Afghanistan Reconstruction is studying where $146 billion aid went.

One should also take into consideration over the deeper reason behind the United States' failure in Afghanistan, which is the lack of a real Afghanistan policy from the beginning, and America's military supremacy. "We realized that our efforts at nation-building couldn't be successful, at least for years and years to come, and we weren't prepared to engage with the kind of forces to ensure a military victory, if that was even possible," said James Warlick, former deputy special representative for Afghanistan and Pakistan.

"Both Republicans and Democrats, Bush and Hillary Clinton, they are all responsible. As well as everybody in the American establishment and American media, for making the war on terror and the fight against the Taliban into this existential thing that it was," said Professor Vali Nasr from Johns Hopkins and former U.S. diplomat for Afghanistan.

There doesn't exist a war that could and should be described as a good one. The biggest mistake that the U.S. committed was that Washington together with the U.S. media had kept telling its people and the whole world how sacred the war in Afghanistan was. The war was launched to prevent further terrorist attacks in the U.S., while in the end it failed to fulfill its original goals.

President Biden could still somehow celebrate his one-year anniversary of the U.S. withdrawal from Afghanistan by honoring all the American soldiers who sacrificed their lives. But what he couldn't miss is that the Afghans are suffering and continue to live under sanctions imposed by the U.S., the country who vowed to save them initially.

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