Strange but true, Art, your last post. Even though the nasty short bombing campaign made us leftists more than somewhat uneasy, it seems to have had a positive effect judging from the happy people in Kabul today. That makes me even more uneasy. No simple answers.
Your other point--that there wasn't a snowball's chance in hell that the US wouldn't make a sharp military response.--is also valid.
I doubt that the innate strategic value of Afghanistan really had anything much to do with it. Having gotten involved in that wasted land now, we are in for a long and difficult process of "what do we do now".