What is "nation-building" in this context? Basically indoctrinating/brainwashing the populace so that they won't become a threat?
After toppling the Taliban, the idea was to build up Afghanistan into a modern state that wouldn't be a haven for terrorists.
The problem was that Afghanistan has never been a unified country. Historically it has always been a collection of miserable warlord fiefdoms, set up in isolated pockets of terrain separated by mountains. Whatever central government existed was weak, and its power didn't really extend out into the far corners of the territory.
Our plan was to shore up the central government and build roads to join the isolated pockets into one larger country. But the central government proved to be corrupt and inefficient, and building roads through mountains is no easy task.
We did a lot better job of nation building in Iraq, but Iraq was already much farther along the path to being a modern state when we started.
The poster child for nation-building is, of course, Japan, where we were able to both force a complete ideological break with the Imperial Japan of old, and set them back on their feet economically, so that they became a prosperous modern country, and a strong ally.
It is not America's right nor obligation to "build nations" or "ensure the world is safe for democracy", nor can they do it; it's logistically impossible for any country. "Nation building" is nothing more than a euphemism installing a puppet regime after overthrowing the previous one. This is what they did with Japan, Germany (which was partitioned between globalist west and soviet east and erased as a military competitor just as they did with Japan) and many such other countries which did not align with globalism, terrorist or not. They make up excuses like weapons of mass destruction, babies in incubators, the rape of Belgium, and other made up imminent threats to justify an invasion. America aligned with regimes which could qualify as terrorist or international threats just as well; USSR, Condor Plan (Argentina, Chile, Nicaragua, etc.), Zionism, Samuel Doe, African regimes, Plutarco ElĂas Calles, Batista, etc. so if it were about values or human rights, they wouldn't have done any of that (not to mention human rights violations at home)
If you want to stop having terrorists, don't hang out in the middle east; it's better to just stick to your own territory and let other countries be; this was pretty much the policy of America until Wilson and they did just fine. I know times have changed, but this is just adding problems where there were none. Why was the US in the middle east in the first place?
Besides, it will fail because their islamic culture is inherently incomptible with western values. There can be no distinction between mosque and state (lol), no respect for "diversity", no such thing as free speech, etc. They never went through a protestant reformation the peace of Westphalia or French revolution.
Feel free to correct me if I got anything wrong.