The dramatic fall of Afghanistan to the Taliban will go down in history as the most spectacular military and political debacle for the US in decades. Even as it withdrew its forces from the country that it had occupied for two decades, the US mishandled and miscalculated as it had done for years. It took the well-equipped South Vietnamese army two years to finally give in after the humiliating US withdrawal, but for the 300,000-strong US-trained Afghan army the collapse took less than a month. On Sunday, the Taliban entered Kabul without a fight. By the evening they were celebrating at the presidential palace. President Ashraf Ghani and top officials fled the country. Millions of Afghans were abandoned by the US and its Western allies. And there were “Saigon moments” on that ominous day: US helicopters hovering over the deserted embassy building to evacuate staff while thousands of “friendly” Afghan collaborators — translators, aides and helpers — and their families hurried to board planes making their final departure from the abandoned city. Amid the pandemonium most will be left to their fate. For the US administration, there is no clear strategy of what to do next. Like his predecessor Donald Trump, President Joe Biden wanted to end this endless war. But relying on the Afghan army to repulse advancing Taliban fighters, even for a few months, proved to be a major intelligence miscalculation. After 20 years, hundreds of billions of dollars spent and tens of thousands of lives lost, the US was out, defeated, with few strategic objectives achieved. Even though Biden had said that the US was not there for nation building, the reality is that successive administrations had hoped that a Western-style democracy in Afghanistan would ensure that the Taliban and other extremist groups do not return to power. As in Iraq, the US failed to understand the complexities of Afghan society and culture. And just like the defunct Soviet Union, the US failed to learn the lessons of history. Afghanistan became the fulcrum of a geopolitical power struggle that even the sole superpower of the day could not untangle. The vacuum left by the US withdrawal will be filled by Afghanistan’s close and distant neighbors. That is how it works. Russia and China will step in at one point or another. The Taliban need recognition if they want to survive. It is not clear how they will govern a country that has been at war for most of the past four decades, and with deep sectarian, tribal and ethnic fissures. Will they share power with local rivals, or will they revert to the authoritarian, autocratic and puritanical rule of the past? And what about Al-Qaeda and other extremist groups re-emerging and regrouping under Taliban protection? What does that mean for the West and the region? What about the fledgling democracy, women’s rights, human rights and freedom of expression? The prognosis is not good and the future looks bleak. Then there is the ideological backlash at home in the US. The fall of Kabul brings a symbolic end to almost two decades of a neoconservative view of the world and of the role of the US that became a foreign policy mantra under George W. Bush. The interventionist ideology that neoconservative icons had pushed under Bush has finally come to an end. The US is exhausted, and the Middle East has become a geopolitical nuisance, a liability, rather than a peaceful sphere of American influence. The interventionist ideology that neoconservative icons had pushed under Bush has finally come to an end. Osama Al-Sharif Will the Afghan debacle signal a slow embrace of selective isolationism for Washington? It could speed up the pivot to a more stable Southeast Asia, to a more strategically vital region like South and Central America, and to a more comfortable and equitable relationship with the EU. Washington’s abandoning of Afghanistan sends a troubling message to US regional allies with their conflicting agendas and, more importantly, to its traditional rivals: Iran, Turkey and Russia. Without direct US regional involvement America’s allies should feel concerned. One thing is certain and that is the reverberations of the US departure from Afghanistan will be felt for years in a region that remains volatile and unsettled, but also equally important to its immediate neighbors, including Europe and Russia, as it battles extreme religious dogma, and sectarian and ethnic divisions amid a desperate search for democracy and egalitarianism. Osama Al-Sharif is a journalist and political commentator based in Amman. Twitter: @plato010 Disclaimer: Views expressed by writers in this section are their own and do not necessarily reflect Arab News" point-of-view