From conservative columnist Michael Gerson's April 28 Washington Post column:

Arizona's new immigration law is understandable -- and dreadful.

Few Americans would happily tolerate living near a porous border with a failed state, or, in this case, a Mexican state that has failed in certain lawless regions. Portions of the border have descended into an arid state of nature -- a vacuum of authority filled by drug gangs, human traffickers, roving vigilantes and desperate migrants who sometimes die in the desert or in drainage ditches. It is offensive to find such chaos under the American flag.

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Under the law, police must make a “reasonable attempt” to verify the immigration status of people they encounter when there is a “reasonable suspicion” they might be illegal. Those whose citizenship can't be verified can be arrested. But how is such reasonable suspicion aroused? The law forbids the use of race or ethnicity as the “sole” basis for questioning. So what are the other telltale indicators?

Gov. Jan Brewer, who signed the law, looked flustered when asked during a news conference the obvious question of how illegal immigrants might be identified. “I do not know what an illegal immigrant looks like,” Brewer replied. “I can tell you that I think that there are people in Arizona that assume they know what an illegal immigrant looks like. I don't know if they know that for a fact or not.” Yet Brewer has ordered Arizona police to be trained in the warning signs of illegality -- signs that she cannot describe. There is a reason no Arizona official has publicly detailed these standards -- because the descriptions would sound like racial stereotyping. And probably would be.

This law creates a suspect class, based in part on ethnicity, considered guilty until they prove themselves innocent. It makes it harder for illegal immigrants to live without scrutiny -- but it also makes it harder for some American citizens to live without suspicion and humiliation. Americans are not accustomed to the command “Your papers, please,” however politely delivered. The distinctly American response to such a request would be “Go to hell,” and then “See you in court.”