Regionalism and multilateralism, from coexistence to collision?

There is no common definition for regionalism because, on a theoretical level, there is no widely accepted idea of the fundamental features of a region. In several studies, it is assumed that a region is made of states that are placed in the same geographical area but it’s controversial how homogeneous an area must be in order to be considered a region. Other scholars prefer to base the notion of region purely on community of language and cultural identity. Yet, there are uncertainties over the meaning of cultural identity. Some authors base the region-building-process on economic forces, so that trade and commercial relations between some states are more intense than those between other states, in such a way that the former are part of the same region while the latter are not. On the other hand, other authors believe that a region can be formed only by means of political decisions that are expressed through preferential agreements between the states. There is also a school of thought that bases or establishes the origin of a region to the presence of an hegemonic power capable of making other states gathering together in a give