like grenades. rocket after rocket lands. over the hill, there is fiercer fighting. and still, the rockets come in. exposed, trudging through land turned arid. the united states identifying the casualty there reported yesterday as chief petty officer jason "c" -- that's basically a d-mining squad. we've seen ourselves, so many american special forces and armored vehicles often going in with the first group of peshmerga in territory. the white house admits they are in harm's way. but it is clear that this will be long and bloody. >> nick paton walsh fort us