Abstract
In this paper, our purpose is to identify the influence of politics for building a metropolitan solidarity. Our purpose is based on a double comparison between France and Spain, two countries that have experienced phases of centralization and decentralization of metropolitan issue. The first national comparison makes us identify ambivalences state policy on the metropolitan debate. A second comparison between two separate metropolitan narratives (Montpellier and Barcelona), allows us to identify the weight of the political variable when observed - over time and the plurality of levels of power - the conditions for metropolitan solidarity. If politics should not be overstated — in the sense that everything could be summarized on politics in the cities, and the economy would be its simple joystick — it should not be underestimated. We propose somehow to put politics back into its place.