"...Michel Foucault refers to this very definition when, at the end of the first volume of The History of Sexuality, he summarizes the process by which, at the threshold of the modern era, natural life begins to be included in the mechanisms and calculations of State power, and politics turns into biopolitics. 'For millenia,' he writes, 'man remained what he was for Aristotle: a living animal with the additional capacity for political existence; modern man is an animal whose politics calls his existence as a living being into question' (La Vonte, p 188).
According to Foucault, a society's 'threshold of biological modernity' is situated at the point at which the species and the individual as a simple living body become what is at stake in a society's political strategies. After 1977, the courses at the College de France start to focus on the passages from the 'territorial State' to the 'State of population' and on the resulting increase in importance of the nation's health and biological life as a problem of sovereign power, which is then gradually transformed into a 'government of men' (Dits et ecrits, 3: 719). 'What follows is a kind of bestialization of man achieved through the most sophisticated political techniques. For the first time in history, the possibilities for the social sciences are made known, and at once it becomes possible both to protect life and to authorize a holocaust.' In particular, the development and triumph of capitalism would not have been possible, from this perspective, without the disciplinary control achieved by the new bio-power, which, through a series of appropriate technologies, so to speak created the 'docile bodies' that it needed.
...Foucault's death kept him from showing how he would have developed the concept and study of biopolitics. In any case, however, the entry of zoe into the sphere of the polis--the politicization of bare life as such--constitutes the decisive event of modernity and signals a radical transformation of the political-philosophical categories of classical thought. It is even likely that if politics today seem to be passing through a lasting eclipse, this is because politics has failed to reckon with this foundational event of modernity. The 'enigmas' (Furet, L'Allemagne nazi, p. 7) that our century has proposed to historical reason and that remain with us (Nazism is only the most disquieting among them) will be solved only on the terrain--biopolitics--on which they were formed. Only within a biopolitical horizon will it be possible to decide whether the categories whose opposition founded modern politics (right/left, private/public, absolutism/democracy, etc.)--and which have steadily dissolving, to the point of entering today into a real zone of indistinction--will have to be abandoned or will, instead, eventually regain the meaning they lost in that very horizon. And only a reflection that, taking up Foucault's and Benjamin's suggestion, thematically interrogates the link between bare life and politics, a link that secretly governs the modern ideologies seemingly most distant from one another, will be able to bring the political out of its concealment and, at the same time, return thought to its practical calling..."
--From the Introduction to Giorgio Agamben's, Homo Sacer, Sovereign Power and Bare LIfe