Pantheon-Sorbonne University
Poirier began to write while in the French Army in 1968. After being promoted to General in 1974, he retired to become an academic specializing in military strategy at Université de Paris (now Pantheon-Sorbonne University l’Ecole des Hautes Etudes en Sciences Sociales (EHESS), Pantheon-Sorbonne University à l’Ecole normale supérieure (ENS) and École nationale d'administration (ENA).