"The United States has entered an era of profound alteration in traditional patterns and trends in the field of energy, Price relationships, rates of use, sources of supply, and, in its broadest sense, national security, all have become areas affected with uncertainty and conflict. With supplies tight and prices rising, the changes are widespread and painful. Although the Arab oil embargo of recent months has greatly aggravated the crisis, the underlying causes lie farther back in the past and hopes of long-term remedies lie well into the future. It would be fruitless here to describe the immediate situation or report on day-to-day efforts to improve it. Events are moving so fast that any up-to-the-minute account would be out-of-date before it could be gotten into print. Instead, let us examine the fundamental trends and forces that have brought this country to its present pass and that can be expected in persist. Although no clear answer can as yet be given, there is reason at least to ask whether we are witnessing the closing of still another frontier—the end of a low-cost, reliable energy supply in the United States. If the answer should be unfavorable, we would have plenty of company. For many years relative prices of energy have been far higher in Europe, as every tourist who has pulled up at a gas pump knows. Western Europe and, to an even greater degree, Japan are vastly more dependent on energy imports than is the United States, with even for oil producers two-thirds of its own requirements (Tables 1 and 2). Uncertainly of energy supply, both in availability at any given time and in quality of service prevails through much of the world. Most of industrialized Europe, Japan, and in fact all but a handful of countries get along n one-half the per capita supply, or le3ss, of what has seemed to be a necessity for Americans, although their growth rates in recent years have far exceeded that of the United States."