Chris Brown (2004, pp. 289) comments on the tension between the notions of political theory and international relations in the Handbook of political theory. Whereas the former notion has a foundation in the “cause and effect” rationale, the latter notion has predominantly developed into an approach of “Realpolitik”. Realpolitik that starts from observed facts, normative or historical approaches rather than scientific methodologies applied in “natural” sciences. The link of this approach to the theory of democracy is obvious, but it is also under a lot of discussion within the disciplines concerned.
One of the corner stones of political theory in international relations is the concept of the “balance of power”. Derived from a rational choice perspective this approach holds that states can only be controlled by other states and, taking this for granted, international relations are built on power relations. Therefore, moving away from a bi-polar balance of power to a multi-polar balance of power will entail some frictions. These frictions might be wars of independence where states attempt to relocate themselves within the new multi-polar world and space. Even “Brexit” becomes a strategic move to remain an independent power in the upcoming new multipolar world. Russia is testing this multi-polar world order right now. The big countries like Brazil, Russia, India, Nigeria and China, (which I abbreviate BRINC) have huge populations, country size and economic potential. From the Arab States certainly Saudi Arabia has the potential and is eagerly beginning to play a more important role in the world arena. Beyond capability it is a question of willingness to get involved in costly matters of world affairs.
In the 1940s, post-World War 2, the entry ticket into the Security Council of the UN required the possession of a nuclear weapon of mass destruction. As this technology and the ban of these weapons is no longer really working internationally, we shall have to rethink the requirement of an entry ticket. A radical solution would be to ban all countries who own nuclear weapons from the international assembly of the people of a peaceful world. In theory this sets an incentive to dismantle the deadly threats of nuclear weapons. As a side-effect, nuclear power plants used to enrich uranium for use in weapons would no longer be necessary as well.
Political theory allows us to rethink the bi-polar world, which is no longer bi-polar for some time now (perhaps only in the psychiatric sense of the word). The multi-polar world has to be prepared. It is a question of political design. The toughest issue is not only the design, but the implementation of the transition to distributed power systems with multiple rising and failing states or actors. It might get ugly before peace will reign. 
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