The Supreme Court hears arguments today on the constitutionality of Arizona’s immigration law, SB 1070. The legal conflict, which centers on the duties and limits of local enforcement of national immigration laws, is provocative. But it is ultimately beside the point, given the practical and political realities of illegal immigration.

As an especially vulnerable border state, Arizona endures what it calls a “seriously disproportionate share of the burden” imposed by the national paralysis on immigration reform. Under the state’s previous governor, Democrat Janet Napolitano, who now runs the U.S. Department of Homeland Security, the state declared that its inability to control its 370-mile border with Mexico constituted an “emergency.”

Arizona’s problems with illegal immigrants are (mostly) real, requiring increased spending for public education, health care and prisons. The question now is whether the Supreme Court will allow the state to compound its difficulties by affirming a law that is unfeasible, politically unwise and economically self-defeating. Given that other states, including Alabama and Georgia, have emulated Arizona’s approach, the court’s answer is sure to reverberate.

According to the Obama administration, Arizona’s “papers, please” policy, which adds state penalties to immigration enforcement, violates the Constitution by running roughshod over federal prerogatives: If every state can set its own course on immigration, chaos will ensue. This reasoning cannot be dismissed. The emergence of wildly divergent enforcement methods subverts the national character of immigration law. What is to prevent another state -- or a municipality -- from declaring itself Arizona’s polar opposite, with a promise of lax enforcement and minimal cooperation with federal officials?

Blocking Implementation

The U.S. Court of Appeals for the 9th Circuit affirmed a lower court ruling blocking implementation of four specific provisions of the Arizona law, including the requirement that local law enforcement officials make a “reasonable attempt” to verify the immigration status of people whom they “reasonably suspect” of being in the country illegally.

The court found the state’s argument unconvincing. It’s hard to fathom how a local police department is supposed to master the intricacies of U.S. immigration law while simultaneously performing its public safety duties. There are an estimated 11 million illegal immigrants in the U.S., yet they make up only a fraction of noncitizens inside the country in the course of a year. In 2010, more than 46 million noncitizens -- tourists, students, seasonal workers, others -- were lawfully in the U.S. on various visas. Requiring local police to sort through the muddle would divert untold hours from the work they are trained to do.

In addition, the law remains an invitation to ethnic profiling. Even the most fair-minded and conscientious law enforcement officer would be inclined to use skin color or similar traits when assessing whom to “reasonably suspect.”

For these and other reasons, the Supreme Court should uphold the 9th Circuit’s ruling in Arizona v. United States.

No matter how the court rules, the conflict in Arizona, as elsewhere, will only be resolved in the political arena. Although recent history isn’t encouraging, there is reason for hope. As the Pew Hispanic Center reported this week, the flow of undocumented immigrants into the U.S. has sharply declined, and the number of people returning to their countries of origin, Mexico chief among them, has increased. In the past three years the Obama administration has deported more than 1 million undocumented immigrants -- a record. Arizona’s law fits awkwardly with these facts.

Rubio’s Role

The Republican Party, the main force behind the Arizona law and its ilk, seems bound to reconsider. Its all-but-certain presidential nominee, Mitt Romney, has recently made a point of appearing with Senator Marco Rubio of Florida. Arguably the Republicans’ brightest Hispanic prospect, Rubio is growing more vocal about a softer stance on immigrants. Meanwhile, agricultural interests in states like Alabama and Georgia, where crops have rotted in the field for lack of immigrant labor, have sought to blunt the harshest elements of their states’ laws. Eventually, the demographic realities of an aging population will encourage a reassessment of the value of young immigrants.

A final thought: President George W. Bush rightly championed comprehensive reform that would have legalized much of the undocumented population over time while increasing border security. Regardless of how the court rules on Arizona’s law, that is still the right approach.

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