Since the Rodney King riots, political piranhas both left and right have been swarming over the carcass of Los Angeles, eagerly biting off large chunks of urban decay to satisfy their electoral appetites. If their rhetoric sounds tiresome after only a couple of weeks, that is because the liberal and conservative idea banks are empty. Their notions were long ago taken out of the think tanks and put into action. They became the policies that govern urban America today.

In recent decades, liberals have controlled Congress while conservatives have controlled the White House. Each faction got what it wanted most, trading away issues of lesser importance. The conservatives-who gained power by accepting the welfare state - got their war on drugs, 1 million prison cells and mandatory minimum sentences. The liberals - who guarded their political viability by feigning support for the drug war - got a larger welfare state, high taxes and business-crippling regulation.

The liberal welfare state encourages babies to have babies and fathers to disappear. Without live-in fathers to discipline them, teen-age boys run wild in the streets and join criminal gangs that provide at least a semblance of male authority.

By subsidizing irresponsible behavior, welfare encourages more of the same, as sociologist Charles Murray argues. Children grow up without models of responsible working adults. They come to associate regular checks in the mail with nothing more than watching television. They get the message that the world owes them a living. For many, that means whoever has a spare wallet, purse or car had better ante up.

Welfare pays the overhead for many of the young criminals stalking the streets. They may not be on welfare themselves, but many take their sustenance from those who are.

Conservatives, however, have no reason to be smug. Their war on drugs created a criminal subculture in inner-city neighborhoods. Poorly educated young men with few adult models of gainful employment, living in the economically decaying central city, are naturally attracted to the prospect of a career selling drugs. Welfare pays the overhead of the criminal lifestyle; drug dealing promises to make it profitable.

Inevitably, though, arrests and convictions pile up, each one further alienating the young men from the world of legitimate employment. They become career criminals, passing from local jails to state prison to the street.

The combined effects of welfare and drug policies created today’s lawless urban society. This lawlessness is implicated in every aspect of the Rodney King affair. King himself is a convicted criminal who was driving with life-endangering recklessness before his arrest. He was confronted by police beleaguered by the seemingly hopeless fight against crime, who had little patience or good will left after the 250-pound King lunged at them. They were acquitted by a middle-class jury, sympathetic to the police because they fear being raped, robbed and murdered by the thousands of career criminals roaming the streets.

When the jury’s debatable verdict was announced, many inner-city blacks - who suffer the most from crime, but who also believe rightly that blacks have been mistreated by white police all too often - spontaneously hit the streets to protest. After 30 years of enduring an ever-increasing crime wave and the endless failed promises of politicians, they too had little patience or good will left. All that remained was understandable anger and outrage.

Unfortunately, the career criminals and hoodlums of Los Angeles also reacted to the crisis. A tiny percentage in the black community, they became the vanguard of the protest. Rapists, thieves, armed robbers and murderers have by their very nature little or no political conscience. Justice is a virtue with which they are not acquainted. But they have learned over the years that when the black community is outraged over injustice, they can cloak their criminal routine in the dress of protest against racism. They can commit violent crimes under the temporary illusion that the larger black community supports them.

The Rodney King debacle was possible only in a nation besieged by violent crime. America’s current crime wave was produced by liberal welfare policies interacting with conservative drug-prohibition policies. Those same liberals and conservatives are now confidently telling us how to get out of the mess they made. These powerful pundits and politicians hover over us, mercilessly striking us with false rhetorical blows as we lie virtually defenseless. Isn’t that a crime?