This passage from Mouffe’s Agonistics is a beautiful and useful thought-jewel:

…We argued that two key concepts – ‘antagonism’ and ‘hegemony’ – are necessary to grasp the nature of the political. Both pointed to the importance of acknowledging the dimension of radical negativity that manifests itself in the ever-present possibility of antagonism. This dimension, we proposed, impedes the full totalization of society and forecloses the possibility of a society beyond division and power. This, in turn, requires coming to terms with the lack of a final ground and the undecidability that pervades every order. In our vocabulary, this means recognizing the ‘hegemonic’ nature of every kind of social order and envisaging society as the product of a series of practices whose aim is to establish order in a context of contingency. We call ‘hegemonic practices’ the practices of articulation through which a given order is created and the meaning of social institutions is fixed. According to this approach, every order is the temporary and precarious articulation of contingent practices. Things could always be otherwise and every order is predicated on the exclusion of other possibilities. Any order is always the expression of a particular configuration of power relations. What is at a given moment accepted as the ‘natural’ order, jointly with the common sense that accompanies it, is the result of sedimented hegemonic practices. It is never the manifestation of a deeper objectivity that is exterior to the practices that brought it into being. Every order is therefore susceptible to being challenged by counter-hegemonic practices that attempt to disarticulate it in an effort to install another form of hegemony.