While some improvements in the Afghan economy are noted, the country is still severely hampered by the need to import much of its basic services. Take cement as an example. Afghanistan imports thousands of tons of cement from Pakistan and Iran every month. Afghanistan produces cement at the Ghori factory, but in low quality and quantity. Two other cement factories still need rehabilitation.
Although the Afghans could be blamed for not rehabilitating the two factories (Jabal Siraj and Herat), the US could work with the Afghan government to find ways such as privatization to rehabilitate such factories and enhance their capacity. Another cement factory was supposed to be established in Jalalabad but that never materialized. Developing this industry will not only help the Afghan economy but will also mean that less cement will be imported from Iran, a country that is essentially hostile to the US.
The same applies to many other construction materials such as bricks, pipes and electrical supplies, to name a few. In all case there is existing infrastructure for producing these items locally and reducing the reliance on imports. However, the businesses that are interested in producing construction materials have been unable to compete with imported materials. All that is needed is assistance with rehabilitation, simple technology improvements and, support -- by letting these businesses know that the US military will be their customer.