THE WORLD HAS changed, provoking heated discussion among international relations observers. The contending theories may seem obscure but the ideas that flow from academic conferences and learned journals represent one of the few systematic attempts to make sense of the new ‘world order’, which harbours international terrorism, global pandemics and weapons of mass destruction.

Like the forces they seek to explain, schools of thinking in international relations represent sharply competing world views. Competition between such schools of thought matters because it generates contending approaches to sound public policy. Theory does not just explain the world – it justifies actions. What follows is a brief summary of some recent theories of international relations vying for legitimacy.