The precautionary principle versus risk analysis.

Precautionary behavior serves a valuable protective purpose as a first response to the new. It causes a quick retreat to the safety of the familiar; it provides time for a realistic "friend or foe" assessment of a new event. This rational assessment is often delayed by the sluggishness of government bureaucratic processes, or stopped by an implied challenge to a status quo. At the public level, reassurance may be slow to overcome an early uncertainty. However, a precautionary response does not provide an operational governing principle, although it makes publicly plausible an indefinite concealment of de facto political actions, or nonaction. The alternative of rational decision making at the policy level should flow from a comparative benefit/cost/risk analysis. Such early risk analyses have pragmatic uncertainties based on the limited available knowledge base and, accordingly, require judgmental application.