Modernity was supposed to be the period in human history when the fears that pervaded social life in the past could be left behind and human beings could at last take control of their lives and tame the uncontrolled forces of the social and natural worlds. And yet, at the dawn of the twenty-first century, we live again in a time of fear. Whether it's the fear of natural disasters, the fear of environmental catastrophes or the fear of indiscriminate terrorist attacks, we live today in a state of constant anxiety about the dangers that could strike unannounced and at any moment. 'Fear' is the name we give to our uncertainty in the face of the dangers that characterize our liquid-modern age, to our ignorance of what the threat is and our incapacity to determine what can and can't be done to counter it.