When the Arizona legislature first passed a law to require immigrants to carry alien registration at all times and to enable law enforcement agents to question people if they have reason to suspect they’re in the country illegally, Florida Republican Sen. Marco Rubio wasn’t quite sure what he thought of it. Eventually, he said he would have voted for it had he been in the Arizona legislature.

Today, though, Rubio said he does not consider the Arizona law a “model” for the nation:

Rubio said he understood why frustration with illegal immigration led Arizona to pass a law allowing local police to demand proof of citizenship. He also disagreed with the Obama administration’s contention that the law is unconstitutional. But he added, “I do not believe (laws like the one in Arizona) should be a model for the country.’’

Rubio’s reservations about the law come at a time when polls show the Republican Party facing a yawning deficit of support among Hispanic voters. Both national parties have launched national campaigns to reach out to the Hispanic community, the fastest growing part of the electorate and the key to victory in a number of swing states.Democrats have been zealously attacking Republican opposition to the DREAM Act, potentially popular legislation that would grant citizenship to the children of illegal immigrants who go to college or enroll in the military. In recent weeks, Rubio has started countering the criticism by proposing an alternative that would allow these children to obtain legal status but not citizenship.

If Rubio is successful in building support for his proposal, he would be helping the GOP kick a potentially losing issue off the election-year table. Critics have said the proposal would create a permanent underclass.

Properly speaking, Rubio is right. The Arizona law is not a model for the nation. It’s a model for other states to adopt as they see fit. It’s still up to Congress and the sitting president to craft a sensible immigration policy that takes into consideration national security, the rule of law, the probable economic contributions of potential immigrants and other factors. Immigration policy is one that has to be set at the national level for obvious reasons. The federal government’s failure to facilitate an immigration system that works justifies state-level attempts to tighten law enforcement. If federal legislators don’t like such state laws, they ought to provide states with a better framework for welcoming legal immigrants and deterring illegal immigration in the first place.