As history has progressed, so has the organization form of human societies : at first humans banded together into tribes, followed by city-states, empires and finally, nation states, which have proven to be the most viable model, and the one in use today in the majority of the world. As each of the previous models had inherent failings and ended up being superseded by the next, so do nation-states : their inherent failure has been the rise of nationalism.
A new political model
Nationalism has resulted in World Wars I and II, both originating from a part of the world rife with national pride and rivalries : Europe. From the ashes of World War II rose the European Coal and Steel Community, whose original purpose was to pool the members' coal and steel resources in order to prevent another war from happening. This regional economic alliance widened and deepened over more than 50 years, and ended up in generating the world's biggest economy and comprising some of the world's most technologically advanced and socially and politically stable states - the European Union. It is an unprecedented political and administrative entity in the annals of history, comprising 27 countries with almost 500 million inhabitants, speaking 23 different languages. It wields considerable influence on the world stage and has the potential of both deepening (taking over more responsibilities from member states) and widening (accepting new members; most likely is Croatia, followed by Turkey and all of the Western Balkan nations; also EFTA, the four european countries currently in an economic union with the rest of the EU). It can be argued that it has been successful, both in economic and social terms - it has brought about increased living standards, security and respect of human rights for its citizens, while acting as a regional factor for stability. Increasingly, the European Union is being seen by states around the world as a viable model of pooling influence and resources for the common good, resulting in the creation or proposal of several organizations modeled on it around the world.