A formal model of crisis-led integration with exogenous crises, path dependence and politicization

This paper develops a formal, dynamic political–economic model of supranational integration in systems of interdependent states. Integration is conceptualised as the outcome of competing functional pressures and political counter-pressures operating under institutional decision-making constraints. At each point in time, integration evolves in response to crisis intensity, cross-border spillovers, endogenous efficiency gaps arising from under-integration, and national crisis-resolution capacities, while being constrained by sovereignty concerns, mobilisation dynamics, identity, and voting rules. The model is formalized through a system of structural equations and a number of parameters, and then empirically explored by means of simulations, made possible by a simulation environment coded into a dedicated app. In the simulation environment, integration outcomes depend on the aggregation of national demands under majority or unanimity voting, and on an endogenous adjustment speed that decreases with crisis asymmetry. The model is explored through simulations calibrated to EU-27 data, comparing symmetric and asymmetric crises under alternative voting rules. The framework provides a unified, formalized account of integration advances, stalemates, and the emergence of self-reinforcing “politics traps” observed in recent European crises.