In Joe Biden’s remarks following the Kabul terrorist attack on Thursday, he concluded: “Ladies and gentlemen, after 20 years it is time to leave Afghanistan.” The moment was horribly circular. America went into Afghanistan in 2001 to drive out the terrorists. In 2021 US troops are exiting the country with the terrorists at their back.

The fact it was Isis-K, rather than al-Qaeda, that was responsible is not reassuring. Isis, and its Afghan branch, did not exist in 2001. The group is both a split off, and a rival, to al-Qaeda. The remnants of Osama bin Laden’s group and its longstanding host, the Taliban, are now relative moderates in the terrorist universe. After two-thirds of a generation and more than a trillion dollars, the tragic events around the Afghan withdrawal offer a measure of the American elephant’s inability to squash the Islamist mosquito.

Biden will undoubtedly attract far more of the blame than he deserves for the closing chapter of America’s longest war. The defeat to the Taliban was a whole-of-government, bipartisan, multiple-presidency operation. But Biden’s name will always be associated with the manner of America’s pullout.