For what reason was the speed limit set at 55-mile-an-hour in 1970’s?

According to recent surveys, a large number of Americans favor increasing the present 55-mile-an-hour speed limit. The current speed limit was set in the early 1970’s when the US faced its first crucial oil shortage. Sixty-five percent of the persons surveyed said that the law was out of date. They pointed to the relative safety of the American highway system and to the efficiency of modern vehicles to support their beliefs. Westerners and younger people, rather than older adults, are more likely to argue against retention of the legislation. The debate is particularly important for those who live in the western states. Many of the large cities in the western part of the country are separated by thirty or forty hours of long, empty, straight roads. People from this area argue that the examples of countries like Australia and Germany should demonstrate that higher speeds are still safe and that speed is disproportionately blamed for traffic problems. Most professional truck drivers favor a higher speed limit. They argue that they can get their goods to the marketplace faster if the speed limit is higher, and that is good for the economy. Since the successful implementation of the turbocharged engine in modern trucks, it is quite possible for trucks to reach speeds twice the legal limit which they are currently allowed to travel. In the end, economic issues may help make the final decision.