at first glance i 'd say Usa but powers are temporary.
the world has never remained to any powerful country. neither glorious roman empire nor supreme ottoman empire and of course wont remain to usa
the most impoortant problem for us to deal with now i think the clash between civilizations. if focus on this problem we ifnd the main reason of this clash is globalism. and defects of our worlds social order. besides affluent countries whose gnp's are very high , poor africaan countries with children who are starving from lack of even basic needs. and this is an order in which wealthies become more wealthy and poors become more poor. who ll take care of poors? this world going to where? indeed this is the most important problem i think. have you ever thought these starving people when you go to restaurant and eat and , dropped the rest of the food that you couldnt eat? anyway that was some thought that come to my mind now and dont bother . you dont need to pay attention just as everyone...