Risk is an inherent component of life; we are all at risk, every moment of our lives, even if we simply stay at home and do nothing. Some risks are self-imposed because we assume that the enjoyment they bring us is worth the risk (cigarette smoking, rock climbing, auto racing); other risks are imposed from natural sources (earthquakes, lightning, floods) or are man-made but considered outside of the realm of the average person's capacity to change (nuclear reactors, satellites falling from space).
It is recognized that the future will be characterized by increasing risks, whether those associated with new technologies, natural or human-caused disasters, or those of irreversible damage to natural systems both regionally (such as acidification, desertification, or deforestation) and globally (such as ozone layer depletion and climate change).
Both private citizens and the public at large are often duped into having risks imposed upon them. The Americans who fought in the Vietnam War were mislead into believing that their presence would curtail the spread of communism; the inhabitants near the Three Mile Island nuclear reactor in Pennsylvania were told that the risk of an accident was virtually impossible; and women who took Thalidomide during the 1950s and 1960s thought that it would stop their early-pregnancy nausea, involving virtually no risk to the foetus.
We accept risks of employment or sport because we consider that the pay, the interest of the activity, or the benefit it gives to others is worth the risk involved.