There are two main problems:

1. The vast majority of the people of Afghanistan are uneducated and illiterate. If you don't have the basic raw materials to work with, an Afghan boot camp is only going to get you so far.

2. The main challenge is not the training of individual soldiers, it's the building of the infrastructure that they need to become a viable fighting force (bases, supply depots, vehicle repair facilities, fuel repositories, roads that connect all of these things, etc, etc). Not only do they have to build these things, they have to staff them (see problem #1).

Bonnieginter, you're forgetting that, before 2001, the Taliban was able to run the country and fight insurgents despite these problems.

The Taliban governed a lot like Genghis Khan. When you use fear as a means of controlling the population, you don't need an army with modern logistical capabilities. People's fear of reprisals prevent them from even thinking about rebellion.

That's why (among other reasons) the insurgency against the Taliban pre-2001 was so ineffective.

They didnt run the country, they tried to destroy it.
Afghanistan has a remarkable history. It has played host
to Genghis Khan, Alexander the Great, Marco Polo, Rudyard
Kipling among others. The Buddhist Statues were a testimony
to their history and resilience. The Taliban destroyed
these statues to demonstrate their contempt for all the
infidels in the world.
I dont think the Taliban will be remembered for providing
safe drinking water in Kabul, or building schools in
rural areas without them.
The taliban "ran" Afghanistan in much the same way the Nazis
ran Auschwitz.

It's true, the Taliban did not provide good governance by western standards. My point, though, is that they were able to provide stability and order despite facing the same challenges the Karzai government is currently unable to meet without the US military.

It's also true that they used ruthless tactics to do so, but this is a primitive country and brutality is the only effective means of establishing control in these circumstances.

I understand what you're saying, and am not accusing you
of being pro-Taliban.
What's ironic is that Afghanistan would be far more manageable for the US if we dropped all pretense of
"nation building"(running the country)in favor of the military objective. We're there to kill terrorists and
deny them access to the territory. Forever.
In order to effectively secure and control the country,
we have to "own" it. In other words, an occupation.
There would be a military governor much like MacArthur
in Japan. The Governor's word would be law. The borders
would be closed. All Afghan nationals would live
in detention centers. run by our military police.
Necessities would be provided for: food, medicine, schools
etc. places to worship.
But this isnt going to happen. It would be long and costly.
I suspect were going to leave in the next 3 years. Then
the chaos will start anew.