Many theories have been developed over the decades to explain the phenomenon of European integration. We are not going to use them all here. The comparison between the European Union and the Soviet and post-Soviet space is only possible to a certain extent. However, in this introductory part we are going to define some integration theories that will be useful to us.
First, we need to define the integrative process in itself. European integration is often seen as the brightest example of “regionalism”. Regionalism refers precisely to the need for state actors to delegate powers to an international organization specializing in a particular field. For example, NATO is an example of regionalism in which NATO-member states have pooled their resources together in order to ensure common security. The reasons which push the actors to do it on the scale of a region are multiple and among them we can cite: geographical proximity, economic or social interdependence or cognitive homogeneity.
The key factor in understanding the phenomenon of regionalism is the need to go beyond the limits of the States' room for maneuver. Thus, for example , Slovenia, a small European state, can obtain a much better result in its public policies if it benefits from the expertise of the European agencies to which it has adhered to by integrating the European Union, rather than by having to create its own national agency.
It is this idea of the interest of States that brings us to the first theory that interests us: functionalism (which today is often called “neofunctionalism” because of the popularity of its theses since its revival at the end of the 20th century).
The central idea of functionalism is to move away from ideologies and to conceive regional integration only as a phenomenon seeking to achieve a specific goal. Therefore the international organization exists to implement a function and achieve a result. David Mitrany, the greatest author of this movement, even considered that the State can be an obstacle to the proper implementation of public policies because it is too ideological. We should therefore create international agencies without ideological character to overcome state inflexibility.
Neofunctionalism was supported by authors like Ernst Haas, who as early as 1958 had noticed the particular character of European integration, which was driven by the adherence to the project by the political and economic elites of the member states. Thus, it made it possible to go beyond Mitrany's reasoning, which was very opposed to the State. With Haas, we can conceive of functionalism as a will of states and not just a response to a need. Leon Lindeberg will then conceptualize the preconditions for the emergence of a regional political integration: he considers that the main institutions (economic, political and social) must be present at the regional level, then it is necessary that the institutions should have the capacity to initiate economic and social programs, and finally, the tasks of supranational institutions must be able to be extended as integration progresses.
It is in the neofunctionalist school that appears, following the work of Lindeberg, the interesting notion of spillover effect. This notion refers to the fact that the more integration is advanced, the more it (directly or indirectly) integrates competences and areas that were not foreseen at the start. We can therefore see that the “integrative” process comes to life and becomes in a way autonomous.
Another theory that will interest us is intergovernmentalism. Regarding European integration, this current is mainly embodied by Stanley Hoffmann, who considers that even if the States decide to integrate into an international organization, they remain the only holders of sovereignty. Thus regional international organizations remain the object of the States and not the other way around. This current fits perfectly into the realistic approach of international relations, a political science approach placing the State at the center of international relations and conceptualizing it as a rational actor making decisions in its interests.
Another author of this current, Andrew Moravcsik, considers that what pushes states to integrate together are the economic benefits of integration, within the meaning of Pareto's law (the economic law of perfect equilibrium leading to the optimal cost of a transaction). Thus, according to him, the European states are integrating together to reduce their transaction costs and to optimize their profits.
Apart from these theories, we also need to conceptualize regional integration according to the adopted model. Here the debate rages on, and it is difficult to say whether the European Union is a Federation or a Confederation (or something new halfway between the two). A Federation is a set of united groups (city-states, federated states, sovereign states, etc.) which have common objectives. Their integration process is very often completed by a constitution. We know that the European constitutional treaty was not adopted by the member states and therefore we cannot consider the EU as a Federation in the classic sense of the term. However, the Court often treats European treaties as a constitutional standard for the international organization and therefore the EU acts as a Federation.
A Confederation is very close to the notion of Federation, the difference being in the fact that in a Confederation the States remain sovereign and that a consensus is necessary to act. The European Union is indeed a Union of Sovereign States but it practices in its ordinary legislative procedure the qualified majority vote of the Member States and therefore does not need a consensus to act. We see again that the EU looks like a Confederation but is not one in all respects.
Karl Deutsch and William Riker consider that the European Union tends towards a Federation and this is all the more evident as the economic, social and ideological-cultural factors of European integration resemble the conditions necessary for a classic federal integration.
The European federal idea is also reinforced by the existence in the EU of a European Parliament, representing European citizens. It is the first step towards a european “deimos” that had been conceptualized by Altiero Spinelli. Moreover, Spinelli had greatly inspired the democratic tendencies necessary for European integration in his “Manifesto Ventotene” of 1941. The democratic question is also strongly linked to the idea of legitimacy, in fact the European Union is seen as being too technocratic and not close enough to its citizens. At the same time, the States do not want to give more decmoratic legitimacy to the Union for fear of losing control.
It is in this movement that the concept of principal / agent is situated. This concept refers to the fact that the “principals” (the States and therefore their Governments) send “agents” to work at the regional level with objectives given to them by the “principals”. Thus one could believe that the European Union is an organization whose staff is made up only of national delegations subject to the wishes of the States. But this is not quite the case in the sense that the “principal” depends on the expertise of the agent and the emergence of a European civil service illustrates perfectly to us that they have a will of their own. They therefore contribute to integration when they think in terms of the Union and not just in national terms.
Finally, with regard to regional economic integration models, we must also cite the Hungarian economist Bela Belassa who determined the stages of regional integration: the first stage is the Free Trade Area (FTA) which corresponds to the abolition of tariff barriers between member states but these retain their right to set tariffs for “third party” states, the Customs Union (UD) which is a step above in which the states agree on a common tariff, then comes the common market which adds to the Customs Union the four freedoms of movement (goods, services, capital and movement of workers), and finally it is conceivable that the last level of regional integration might be Political Union.