Twenty years ago, a major terrorist attack against the U.S. homeland shocked a country many imagined to be as indispensable as it was exceptional. Today, it seems almost fitting that the United States should mark the 20th anniversary of that attack under the shock of the ignominious end to the intervention in Afghanistan. Whether shock will be enough to prompt a reckoning with the mistakes of the past 20 years, though, is far from certain.
That reckoning is necessary, because if the interminable global war on terror that followed 9/11 prevented another terrorist attack on the U.S. homeland, it did so at huge cost. While most of America is naturally reflecting this week on all the different ways the 9/11 attacks transformed country and the world, what seems to have changed most is our understanding of the impact and limits of the kind of military power unleashed over the past 20 years.
There is widespread agreement that the U.S. export of industrial-scale violence will continue to reverberate across wide swaths of the Middle East and South Asia for another generation to come. From the toppling of the Taliban 1.0 regime in 2001 to the rise of the Taliban 2.0 in 2021, Afghanistan has consistently ranked at the bottom of global indexes on the state of peace and conflict, right alongside Iraq, Yemen, Syria, Pakistan and Somalia. In all six countries, American boots on the ground—both overt and covert—have been a defining feature of a torrent of violent dysfunction that has killed and wounded millions. And if we take U.S. President Joe Biden at his word that “over the horizon” strikes against U.S.-defined terrorist threats will continue long into the future, many more will perish.