The roots of the first great economic crisis of the 21st century.

Summary This thesis aims to rehabilitate the circuitist analysis of economic crises. This theory has been largely supplanted since the end of the "glorious thirties" by neo-liberal thinking, but even the most recent models emanating from this thinking have not been able to prevent or cure the crisis we are experiencing. We therefore consider the theory of the circuit, of which Marx and Keynessare eminent representatives, as being much more capable of apprehending the current crisis. We establish a dichotomy in economic analysis between circuit analysis and liberal analysis, which we also call in this thesis "market analysis". We will show how this analysis is constructed and how its assumptions are developed. This work also carries out an empirical analysis. We will show, in the light of circuit theory, the consequences of neoliberal policies on economic dynamics. These trade and financial liberalization policies were supposed to lead us towards a general equilibrium of full employment. However, they have, on the contrary, led to the generalized imbalance of underemployment. The conclusions of this thesis in terms of economic policies are in favor of a reasoned and concerted protectionism at the international level, as well as in favor of controlling the financial system so that it finances the accumulation of capital by non-financial corporations.