Americans should demand more from their public policy makers than bumper-sticker rhetoric like "What part of illegal don't you understand?"

As the national debate about immigration policy moves off the back burner, Americans should be wiser than many of their leaders, including those in Arizona who in April passed the strict and simplistic immigration law that brought the controversial issue to the forefront.

Next week, the U.S. Justice Department will begin arguing in federal court for a temporary restraining order to stop Arizona from putting its new law into effect on July 29.

The state law requires local law enforcement officials to check the immigration status of people "where a reasonable suspicion exists that a person is an alien who is unlawfully in the United States." That "show us your papers" order should be anathema to every American.

In bringing suit, the Obama administration made a risky political calculation. National Latino and civil rights organizations already had filed similar lawsuits contending that immigration policy is a federal role that trumps state or local law. The administration could have let them carry the ball; instead, it intervened directly.

It was the right decision, even though some Democrats cringed that it wasn't politically wise in an election year. This is a profoundly important civil rights issue, made all the more obvious by Republicans trumpeting the issue of "states' rights."

Wasn't that battle cry buried with George Wallace and Lester Maddox?

Apparently not. Two Republican senators from southern states — Jim DeMint of South Carolina and David Vitter of Louisiana — have proposed an amendment to a Senate bill set for debate next week that would bar the federal government from blocking implementation of the Arizona law.

Then there's the fear-mongering of Arizona Gov. Jan Brewer. She declared that a "majority" of illegal immigrants smuggle drugs into the country and that illegal immigrants have caused a huge spike in violent crime, including beheadings and kidnappings.

Federal, state and local law enforcement authorities say crime statistics bear no such evidence.

Border states and, indeed, the nation need more federal resources to combat immigration-related problems. The Obama administration has added millions of dollars to the Department of Homeland Security operations along the international borders and audited payroll records of more than 2,900 companies that resulted in more than $3 million in fines and firings of thousands of illegal immigrants.

For almost 25 years, the nation has needed sound, effective immigration reform that deals sensibly with illegal immigration as well as workplace enforcement, legal immigration, economic needs and border security.

But now, with polarized lines drawn, any prospect of thoughtful, fact-based immigration reform seems like a pipe dream.

People migrate here to work. The legal foreign-born population in the United States outnumbers illegal immigrants more than 3 to 1.

They come here to teach, practice medicine, open businesses and work in hotels and restaurants. You encounter them every day.

Simplistic solutions like Arizona's ignore the dozens and dozens of ways that people come to the United States, from political refugees to foreign student visas to family ties. What part of legal don't you understand?

Most Americans, including street cops, have no clue about the legal complexity and inefficiency of the U.S. immigration system. Beat cops have enough challenges without requiring them to decipher Byzantine civil immigration codes. Let the cops be cops.

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