Many streets in America's big cities are in a state of anarchy. Too often the police are overwhelmed. In some cities and neighborhoods, people are afraid to go outside. And in and out of their homes, they risk murder, assault, rape, holdups, muggings and theft.

The reason is that the United States is in the grip of the third of three great crime waves. They began about 50 years apart - approximately 1850, 1900 and 1960 - and each has lasted for 20 to 30 years. The current wave is more serious than the last one, which Prohibition helped sustain into the early 1930s.Each year in this decade, about 20,000 Americans have been murdered, mainly in street fights, family quarrels and robberies. Most have been young men, half of them black. In some Northern cities, blacks are 20 times more likely to be murdered than whites.

Our crime waves stand out against the long-run trend of declining personal violence in Western society, which the cultural historian Norbert Elias attributed to "the civilizing process." By that he meant the restraint of aggressive impulses, acceptance of humanistic values and establishment of ordered routines of life that minimize occasions for violence.

America's three great crime waves can be linked to immigration, economic deprivation and war, which all interfere with the civilizing process.

Every major war has been followed by a short, sharp peak in violent crime in the countries of most of the belligerents. Our current crime wave appears to have been exacerbated by the Vietnam War.

In any case, the first and second episodes of violent crime wound down as immigrants were incorporated into the expanding economy. Reforms in policing and criminal justice policy made arrest and punishment more certain. Civic associations and reform movements transformed crime-ridden neighborhoods and cities. Other institutions, especially churches, reasserted conservative moral values that heightened inhibitions against violence.

Today's epidemic will not go away without similar concerted action. Multiple concurrent strategies are needed to undercut conditions that breed and sustain crime.

The poverty cycle must be broken.

More-certain justice for repeat offenders is essential. Community efforts in every neighborhood threatened with crime are also crucial. This requires public support for self-help projects such as teenager employment programs and for citizen crime patrols. Comprehensive drug control and rehabilitation programs are indispensable.

Unless we mobilize money and people to pursue these policies, today's crime wave will be our longest and most costly, and more streets will become nightmare alleys.

(Ted Robert Gurr is professor of political science at the University of Colorado. He is editor of the forthcoming book "Violence in America: The History of Crime.")