- The European Union is a parliamentary system which elects multiple parties, in changing coalitions. Arguably this makes for a more diverse debate on some issues than within the USA, which has 50 states but only two relevant parties.
- The EU does not have a unified military. Each nation has its own defense forces and joint action is usually taken through NATO or UN actions.
- Each nation has it's own constitution. Even though American states have a lot of independence, they all follow the same constitution. There are, however, minimum conditions concerning the adoption of human rights to be able to become a member of the union.