There is room for debate as to whether or not the United States should ever have gotten involved in Afghanistan. Even if you acknowledge (as I do) that there is a legitimate place for countries, as well as people, to help those who are suffering, we do have a most embarrassing propensity for blundering into places with little to no knowledge of the culture, to their detriment and ours.
But once there, how many times can we promise people our help, accept the sacrifices of those who put their lives and families on the line for us, then decide it's too much trouble to keep our promises—how many times can we do this and still have any friends (or integrity) at all? Ask the Hmong, ask the Kurds, ask the people of Iran, ask the Native Americans for that matter.
It's like making marriage vows and bailing when life gets difficult. Oh, wait—we do that a lot, don't we?
I also get that sometimes you have to leave an impossible situation, but surely we could have had a better exit strategy. We should have issued humanitarian visas and begun evacuating people long ago, in an orderly fashion, while we still had time, not after the Taliban had taken complete control. Not that we could have evacuated every girl, woman, and Christian in the country—but we certainly should have been able to do better than we did for those who worked alongside us for so long.
Someone I know recently wrote a LONG commentary on the situation. He's a civilian who worked as a military consultant in the region for a number of years. He pointed out a few things that helped me understand the situation better than the (very biased) media. First, the "war" ended several years ago. The country has free elections, successfully updated laws, etc. Second, for 12-15 years, the US has been buttressing the military in this country, training them to rely on an "air only" military force. The country does not have an education system in place for their own people to learn to handle the weapons/tech in place. They haven't had time. They haven't built up their own universities. We've been training and/or coordinating their military work. Third, he acknowledged this is a handicap for the natives. He wrote this before we pulled out abruptly, acknowledging he didn't see an easy way for the US to extricate itself.