What an odd question! Surely everyone accepts the need to regulate nuclear safety? Only economists would think of querying something so obvious! Naturally we have no intention of claiming that the need for state regulation in this field is a recent discovery. The value of economic theory resides in the analytical process it offers for this purpose. In terms of methodology it always starts from opposition to state intervention per se. Such intervention is always open to question and the first thing an economist will ask is why the market is not sufficient in itself to solve the problem. This does not necessarily reflect an ideological preference, on his or her part, for the invisible hand or outright rejection of public intervention, but simply the knowledge that economic theory has identified specific conditions in which the market is not an effective means of securing the general economic interest, in other words maximizing wealth for the whole of society. Externalities, such as pollution, or a public good, such as national security, are the main impediments to market efficiency. If there is no market failure, there is no justification for public intervention. But economists also know that the state – be it embodied by planners, regulators or legislators – has weaknesses of its own, and that public intervention is not perfect. It is easy to summarize what economic theory prescribes with regard to regulation: resorting to the visible hand of the state is justified if, and only if, the defects of public intervention are less than those of the market it sets out to correct. In short, the benefit of public intervention must exceed its cost, otherwise laissez-faire is the only option and one must make do with an inefficient market. (Unless, of course, the means can promptly be found to reduce the cost and inefficiency of the visible hand of the state.)