In a country that defines itself by ideals, not by shared blood, who should be allowed to come, work and live here? In the wake of the Sept. 11 attacks these questions have never seemed more pressing.On Dec. 11, 2001, as part of the effort to increase homeland security, federal and local authorities in 14 states staged “Operation Safe Travel”---raids on airports to arrest employees with false identification (身份证明). In Salt Lake City there were 69 arrests. But those captured were anything but terrorists, most of them illegal immigrants from Central or South America. Authorities said the undocumented workers' illegal status made them open to blackmail (讹诈) by terrorists.Many immigrants in Salt Lake City were angered by the arrests and said they felt as if they were being treated like disposable goods.Mayor Anderson said those feelings were justified to a certain extent. "We're saying we want you to work in these places, we're going to look the other way in terms of what our laws are, and then when it's convenient for us, or when we can try to make a point in terms of national security, especially after Sept. 11, then you're disposable. There are whole families being uprooted for all of the wrong reasons," Anderson said.If Sept. 11 had never happened, the airport workers would not have been arrested and could have gone on quietly living inAmerica, probably indefinitely. Ana Castro, a manager at a Ben & Jerry's ice cream shop at the airport, had been working 10 years with the same false Social Security card when she was arrested in the December airport raid. Now she and her family are living under the threat of deportation (驱逐出境). Castro's case is currently waiting to be settled. While she awaits the outcome, the government has granted her permission to work here and she has returned to her job at Ben & Jerry's.According to the author, the United States claims to be a nation ________.