Being raised in a family of military veterans, Passy described in his autobiography how he "might easily have been drawn towards militarism". Instead, the stories about the horrors of the French conquest of Algeria pushed him to consider the effect that war had upon humanity. Years of violent discontent in Italy, Poland, and Austria and Prussia led to calls for a Europe federation from prominent liberals and socialists: Pierre-Joseph Proudhon, Émile de Girardin, Passy, and Michel Chevalier were all advocates of this idea. In 1859, Passy condemned the idea that military action could be a solution to political issues, suggesting instead that Europe should have a "permanent congress to oversee the general interests of humanity" and an international police force.