by tom sanderson. he is co-director of the transnational threats project at the center for strategic and international studies. so what purposes do these videos serve? >> well many-- well, many purpose, one, it certainly is designed to terrorize the west, the populations, the public is representing that particular individual potentially in the hope that isis deter further action. these groups know, especially isis know that some nations pay ransoms to release their individual, and they know that if they present this as the option for not paying a ransom that perhaps they could split the coalition, the partners that have signed up to confront isis, so that's one reason, terrorizing and potentially splitting. the other certainly about empowerment, both for themselves and for those young men that they try to recruit. at this point in the current state of the battle the u.s. can hit isis with impunity, will have drones in the battle. we have aircraft now. we don't have boots on the ground. so isis can't hi

and among our guest tomorrow we'll focus on the isis strategy with tom sanderson and we'll check in withe president of the university of michigan. we continue our big ten series on c-span. we'll travel to columbus, ohio, for ohio state university and then travel to what many call happy valley as we talk to the president of penn state university. that's all this week. big ten college tour. thank you for joining us on this sunday. i hope you enjoy the rest of your weekend and have a great week ahead. your boss about income inequality, saying this is a driving issue in this campaign. we track the races and debates, it has not been a leading issue, why? >> that is a good question. i think what he said in that essay was it is really the fact of income inequality, not the .dea of income inequality the driving issue in this