KABUL, Afghanistan (AP) — The Taliban are trying to keep discipline over thousands of young fighters who bring heavy-handed methods of war into their new roles as security forces in Afghanistan. Those young men have known only war, most have no schooling and cannot read or write. In the capital of Kabul, many are afraid of them. On a recent night, a Taliban security guard at a checkpoint in Kabul opened fire on a car carrying a family home from a wedding, killing 25-year-old Zainab Abdullahi. The Taliban say it was a mix-up between guards. But the shooting highlights a dilemma facing Afghanistan’s new rulers.