I know you are an idealist. I respect that. I know you are concerned for the women and girls in AFG, and what their life would be like under Sharia Law. That said, AFG is not a US possession. It is ultimately up to the Afghans who runs their country, you seem to imply that the US can keep the government in control for a cost-effective and reasonable annual $10b of "foreign aid", and about 20 US combat deaths, not to mention the horribly maimed.
Bottom line:
The US military effort in AFG was not low cost, the cost in blood and treasure was NOT worth it to Americans. The US is NOT the world's police force. The US does NOT do nation-building well. The Taliban would NEVER stop fighting, and most Americans oppose "endless wars". I have an active duty grandson, and I do NOT want him going to AFG, nor anyone else's loved one. Ultimately its up to the Afghans who controls their country. If it becomes a rats nest of terrorists, we have advanced weapons to deal with them.