Although the old Franco-German engine seems to have taken on a new European political dynamic since Autumn 2002, its legitimacy has been increasingly questioned by other member States who are ever more critical about Franco-German bilateralism, especially regarding matters of foreign and security policy. Indeed, an enlarged Europe faces a dilemma, just as France and Germany. Although any misunderstanding between Paris and Berlin could block the progress of the EU, other member States still show their strong opposition when these two countries constantly agree on European policy issues and make use of their demographic weight.

This could well be a serious obstacle to European integration and a real and long-lasting threat for a majority in favor of France and Germany. The stance taken by these two countries over the Iraqi crisis and their common initiatives in shaping both the Common Foreign and Security Policy (CFSP) as well as the European Security and Defense Policy (ESDP) are clear reflections of these contradictions. Similarly, timelessness of Franco-German leadership and the obtaining of a majority in favor of Paris and Berlin imply that France and Germany base ESDP on a permanent tri-lateral foundation that includes the United Kingdom. The success of such a tri-lateralization of co-operation depends greatly on the existence of constructive relations with the United States. A majority of European Union Member States (especially other 'great States') will accept and legitimize ESDP only if it brings forth a compromise between Berlin, London and Paris.