claiming a significant blow against the islamic terrorist group known as isis. the u.s. says that kurdish forces backed by u.s.-led air strikes have pushed isis out of 90% of the town of khobani, a serious reversal for isis which fought desperately to control the city. the air strikes began in august, and david martin has managed to get a rare look at how theow targets are chosen. >> reporter: the target was a poultry farm that isis had turned into a staging area. it was located in syria, but the planning for this strike and hundreds like it was carried out some 6,000 miles away at shaw air force base in south carolina. >> over here. >> reporter: cbs news was given an inside look at the targeting center where intelligence analysts pour over satellite photos. >> in a way like a detective does, we put together thethe picture with all these bits of intelligence. >> reporter: in a typical week staff sergeant penny and each of