Theories seek to provide a useful framework through which we can better gauge and conceptualize where and how the EU is changing. By chronicling the EU's integration through theories, we seek to understand why States behave the way they do.
Theorizing on European integration has proven to be a slippery and elusive undertaking. One major reason for this is the diversity of the subject matter involved. Every individual EU member has its own rich and long history as an independent State, developing in conjunction with but independently from the other States around it. Another reason is the changes that continue to occur in the political landscape over time. Post-WWII Europe was not the same as Cold War Europe, and Cold War Europe was different still from the Europe of today. This makes it extremely difficult to stay with only one theory of European integration over time. As Europe changes, so too must the policy analysis that seeks to understand it.
Yet another thing that makes theorizing about European integration so difficult is what it seeks to determine. The benefits of most theoretical models are that they might one day help predict future actions or behaviors. Each of the major theories discussed below has been the predominant theory at some point in time, but due to real-world monkey wrenches thrown into their theoretical framework, several earlier theories have given way to newer theories. The European Union can be described as a "moving target" that "(h)as a habit of throwing up new and unexpected facts which wrong-foot extant theories" (Hooghe, 108). The ever-changing political, social and economic preferences of individual member States and their populations makes it nearly impossible to rely on one theory of European integration indefinitely. Rather it seems to be a process of trial and error, in which theories that are bent too far to explain shifting circumstances may be eventually broken altogether and replaced by newer, more accurate ones.
Each major theory would seem to have its own prediction for Europe and the integration project. Neo-functionalists would likely argue that the current crisis will result in increased social pressure by populations on governments to strengthen EU economic institutions, in order to prevent this kind of recession from happening again. They would favor the creation of new 'Euro-bonds' and a permanent European stabilization fund. Under this theory, economic pressure will continue to "spill-over" into other areas of integration (such as social policy) and thus will ultimately result in a stronger, more unified EU than before.
Alternatively, Intergovernmentalists would take a very different view of the current situation. They would argue that the Empty Chair Crisis was actually the beginning of states openly re-asserting their sovereignty, and this latest financial crisis will result in more of the same. Countries dissatisfied with the inability of the EU to financially prevent weaker countries from defaulting and requiring a bailout will likely continue to push for more nationalistic (and less federalized) economic policies. In the opinion of many Intergovernmentalists, "neo-functionalists (have) underestimated the resilience of the nation state" (Pollack, 19). The EU as a supranational authority will be left weakened as rational State actors seek to protect their own domestic interests internationally.
Alternatively, Liberal Intergovernmentalism examines national preferences of domestic constituencies and views national governments as the rational actors who negotiate their respective preferences. Under this model, the current crisis would likely spawn different reactions in different States, depending on whether they were helped (as many Eastern European countries and Ireland were) or hurt (as many Western countries were) by EU integration.
The importance of social demands by constituents of individual states is highlighted by the Constructivism Theory of integration. Under this model, "human agents do not exist independently from their social environments, and its collectively shared system of meanings" (Pollack, 24). Thus, the outcome of the financial crisis is viewed here as resulting in not merely rational-choice State outcomes, but decisions that reflect the cultural, individual preferences of each EU member.
Ultimately, these integration theories will continue to change over time as a young EU seeks to refine what level of integration is desirable for its member States.