The Taliban/Al Qaeda was routed, by the way. The US (and its Allies) moved an entire invading and occupying force to Afghanistan, half way around the world, killed tens of thousands of Taliban psychos, dismantled Al Qaeda, put bin Laden on the run, and effectively ended the threat to Americans of Islamic terrorism.
Your suggestion that the US military is "clearly incapable" of defeating the Taliban is somewhat disgusting and factually inaccurate. The only "clearly incapable" component is the ability of Afghans to live in any kind of democratic society. They don't want it. Some cultures/people seem to prefer living under oppressive, dictatorial regimes where they are told what to do, when to do it, and how they should think. Look at Russia, for example. Russians crave being told what to do, and what to think when they get up in the morning. Russians will kill for their right to be subjugated serfs. Afghans, and many other inhabitants of Middle Eastern countries, are no different. Any mistakes the US made during the duration of the Afghan occupation -- which could hardly be called a "war" after 2012 -- were in failing to realize Afghans truly wanted Islamic whackjobs dictating what goes on in the country. Go figure.