>> there's a whole generation of chechens who grew up with their families being displaced, relatives being killed, and so on. >> reporter: thomas deweil has studied and written about the region. >> for most people that's just a traumatic experience, but obviously for a small minority this is something that is in their dna, that drives them. >> reporter: and like many displaced chechens tamerlan may have struggled to fit in. chechnya is still home to militant separatist groups. and the home tamerlan's father grew up in has been destroyed by war. the relatives still live here. tamerlan traveled here during his trip last year. >> translator: he came to see me. we talked. i said, come here, guy. are you studying, i asked. i'm studying, he said. there was nothing criminal about him. >> reporter: deval says this region has also seen a growth in islamic extremism, becoming more