How can membership of IGO’s gives some countries political and economic power?

The involvement in an IGO such as the IMF or NATO can give a country either soft or hard political and economic influence over another. This political influence, in line with World Systems theory, can often lead to the exploitation of nations for resources and goods meaning that unfavourable trade links are developed leading to increased political cooperation between nations; this cooperation often comes from ideological similarities, or leads to these similarities. Consequently, political and economic power arises from the ability of members of IGOs to either influence SAPs through the IMF, or through military threat associated with IGOs such as NATO, thus leading to economic dominance of MEDCs over poorer countries which are not as influential in IGOs.