What is the role of the Big Powers in the world

A great power is a country that has the ability to exert its influence on a global scale. Goverment of this country  has economic capability, political stability  and military strength. Today we can see a multinational forums like  the European Union and the Group of Eight. Countries of G8 have heavy responsibility for whole world because of their nuclear weapons and large economies.The top of major powers in the world are expected to resolve tensions around the world and promote peace. I think everyone have to know: significant  powers have existed throughout history, it is important part of our life, with Big Powers we can  work out solutions to global problems together