There are actually 20-seven member states that have conferred powers upon the EU institutions (other nations are tied on the EU in other ways). In exchange for conferring competences, EU states are assigned votes from the Council, seats in Parliament in addition to a European Commissioner among the other matters. https://europeanparliament64319.humor-blog.com/26864798/icc-seeking-arrest-warrants-for-hamas-leaders-and-israel-s-netanyahu