president-elect donald trump says he will move immediately to deport or imprison two million, maybe three million, unauthorized-immigrant criminals. <u+201c>what we are going to do is get the people that are criminal and have criminal records, gang members, drug dealers,<u+201d> he said on sunday on <u+201c>60 minutes.<u+201d> like many of his proposals, this one sounds tough and straightforward, but makes no sense under scrutiny and is frightening to think about. start with the fact that the target number is made up. there simply aren<u+2019>t as many criminal immigrants as he imagines. according to rough estimates by the migration policy institute, of the country<u+2019>s 11 million unauthorized immigrants, about 820,000 have criminal records. about 300,000 of those have felony convictions and are presumably the bad people mr. trump is talking about. if he deports those and only those, it will be a remarkable display of law-enforcement discretion, since he said that there were lots of <u+201c>terrific people<u+201d> among the unauthorized who might be allowed to stay, <u+201c>after the border is secured and after everything gets normalized.<u+201d> and yet he also said that two million to three million would go , a population about the size of chicago<u+2019>s. he would have to haul away a lot of terrific people, and terrorize many more, to hit that mark. this would require a vast conscription of state and local law enforcement against people who pose no threat. it would mean a surge in home and workplace raids, investigations and traffic stops. it took the obama administration eight years to deport 2.5 million immigrants. the threat of mr. trump chasing that number right off the bat is the reason immigrant communities are so terrified. but the damage won<u+2019>t be immediate: he can<u+2019>t just load two million people onto buses and planes and ship them out. he<u+2019>ll first have to stuff them into the bottleneck of the immigration courts, where there are too few judges and lawyers for a swollen caseload, and fill detention cells to bursting. mr. trump may be unaware of due process, or in denial about it, but it exists. all the while he would be snatching workers from their jobs, workers who keep the economy humming. then there is the policing problem <u+2014> indiscriminate roundups in immigrant communities cause crime victims to fear and avoid the police, and crime to fester. we<u+2019>ve been down this ugly path before. arizona followed it for years under sheriff joe arpaio of maricopa county, a trump ally who broke the law, abused civil rights and neglected other law-enforcement duties. it took years of struggle by human rights advocates, in the streets and the courts, but voters finally ousted sheriff arpaio in this month<u+2019>s election. how can the country resist if mr. trump tries to nationalize the arizona model with mass deportation? much of the response will have to be local. the list of cities where leaders and police officials have vowed not to participate in a trump dragnet is long and growing. immigration is a federal responsibility, they say, and they will not waste policing resources, money or time on a destructive plan that won<u+2019>t work. <u+201c>that is not our job, nor will i make it our job,<u+201d> said the los angeles police chief, charlie beck. mayor bill de blasio of new york struck the right note : <u+201c>we are not going to sacrifice a half-million people who live amongst us, who are part of our communities.<u+201d> that<u+2019>s the kind of determination that public officials will need to summon. if mr. trump begins a senseless purge, all segments of society <u+2014> religious congregations, factories, farms, colleges and universities , private individuals <u+2014> will need to speak out and defend the vulnerable. day laborers <u+2014> the likeliest victims of harassment and vigilantism <u+2014> will need to be protected. mr. trump and his republican allies in congress have threatened to cut off federal funding to immigrant-friendly <u+201c>sanctuary cities<u+201d> like san francisco, chicago and new york. it<u+2019>s unclear what budgetary pain they can cause. but we can only hope that these places stand firm at a time when cherished american ideals are under siege. follow the new york times opinion section on facebook and twitter (@nytopinion), and sign up for the opinion today newsletter . a version of this editorial appears in print on november 18, 2016, on page a30 of the new york edition with the headline:  mr. trump<u+2019>s plan to purge the nation. today's paper | subscribe
donald trump<u+2019>s plan to purge the nation
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