New Islamic Caliphate

ISIS has changed its name and declared its leader the new caliph--successor to Muhammad. According to Muslims sites there are 3 ways of becoming a Caliph--election by leaders, appointment by a prior Caliph, or brute force. With the new Caliphate Muslims (at least the ones that recognize it) are obligated to obey and they can now state offensive wars, rather than the alleged defensive ones. However, this all depends on the Caliphs recognition in the Muslim world, but even if he gets SOME recognition it will be incredibly damaging.