As U.S. leaves, a struggle to train Afghan army

(CBS News) In Afghanistan, a man in a police uniform fired on NATO soldiers Sunday, killing three of them.

Problems and challenges continue for both the Afghan police force and the army, as the U.S. prepares to leave. Training them has not been easy.

While U.S. Marines stand back to observe, Afghan National Army officers instruct new recruits in marksmanship. There is also little input from the Marines while an Afghan lieutenant outlines a mock ambush. And that's part of the plan.

U.S. Marines in one truck play the part of Taliban insurgents. The Afghan National Army executes an ambush, penning the insurgents between two lines of fire. Marine General Mark Gurganus admits, though, the Afghan troops still have a lot to learn.

"It's always difficult to start with, because you're starting with a pretty small baseline of expertise," Gurganus said.

The Afghan soldiers say they are still reliant on U.S. forces. .

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"If the Marines provide us with better training and equipment," said Lt. Asdullah Rahim through a translator, "then we will be able to defend our country."

It's not just weapons and tactics the Afghans need. The Afghan forces face huge challenges in leadership, logistics, and supplies.

"The biggest challenge is trying to build an army while trying to fight a counterinsurgency," Gen. Gurganus said.

Pulling soldiers off the battlefield to learn from other Afghans instead of U.S. forces is a crucial step in their development, according Gen. Gurganus.

The most difficult problem the Afghan National Army faces has nothing to do with guns or tanks: It's illiteracy. About 86 percent of the Afghan army can't read or write. Teaching soldiers those basic skills may mean the difference between success and failure, because in two years, the Afghan National Army will be on its own.