World politics has been surprised recently by two sudden developments. The first took place around the beginning of 2007, when the question of global warming rose abruptly to the top of the agenda, after having been a factor in the background. The second occurred in the autumn of 2008, when the rules for a global economy started inspiring great anxiety, after having been regarded as a source of stability. These two shifts took place independently, but their consequences will require common management. The regulatory structure underlying the world's economic, legal, and political systems needs to be revised. This presents the EU with the greatest challenge it has ever faced. The point is that this global challenge comes on top of the pr- lems already posed by markets, welfare states, security, energy, and movements of population. The additional challenge is furthermore of such a kind that a deeper discussion of the very structure of the Union is difficult to avoid.