Where does political ecology lie on the left-right spectrum? What does it mean? Andrew Dobson indicated that the analyses of ecologism assign him four possible positions: a new global order (symbolized by the Brundtland Report), a centralized authoritarianism (Garrett Hardin's "tragedy of the commons"), the authoritarian commune (for which Goldsmith is frequently the symbol) and an egalitarian and participatory anarchism. This book questions the validity of this standpoint, by examining how ecologism confronts the other ideologies in the context of France: liberalism, socialism and conservatism. Three conclusions emerge: the danger of an "ecofascism", which risks not being ecologist if the ecological stakes are not taken seriously; the contribution of ecologism to an emancipatory criticism of modernity, not to be confused with a retrograde antimodernism; and the difficulty shown by analysts and actors alike, to grasp this trend.