Afghans revere poetry, particularly the high literary forms that derive from Persian or Arabic. But the poem above is a folk couplet-a landay, an ancient oral and anonymous form created by and for mostly illiterate people: the more than 20 million Pashtun women who span the border between Afghanistan and Pakistan. War, separation, homeland, love-these are the subjects of landays, which are brutal and spare, can be remixed like rap, and are powerful...