when u.s. forces last went to iraq, myspace was the next big thing in social media. remember tom was everyone's friend. hey, tom. haven't seen you in a while. as president obama now contemplates action in that country again, the battle isn't only in iraq. it's online as well. sunni militants are coordinating a pretty astonishing social media offensive from wait toer to mobile apps. this week, they launched a youtube video that features british and australian fighters appealing to western muslims to join their jihad. nbc news hasn't independently verified that video, but it is causing waves. so how is social media reshaping the field of battle? clay is an nyu professor who specializes in these technology questions. clay, thank you for joining us.