Dear Editor, Given that that new Arizona immigration law (Senate Bill 1070), effective July 1, prohibits racial profiling, should we assume that anyone in Arizona (residing or visiting) who attracts the attention of law enforcement officials could be asked to show ID proving U.S. citizenship? A driver's license is not proof of U.S. citizenship. Therefore, can we assume that we have to carry either a U.S. passport or birth certificate when in Arizona – just in case? If so, must we assume then that Arizona will be the first and only state in the U.S. in which we must carry a U.S.-issued passport or birth certificate to cross the state line, just as we must do when traveling to Canada, Mexico, or any other foreign country?