According to Massey, the rise of America’s large undocumented population is a direct result of the militarization of the border. While undocumented workers once traveled back and forth from Mexico with relative ease, after the border was garrisoned, immigrants from Mexico crossed the border and stayed.
“Migrants quite rationally responded to the increased costs and risks by minimizing the number of times they crossed the border,” Massey wrote in his 2007 paper “Understanding America’s Immigration ‘Crisis.'” “But they achieved this goal not by remaining in Mexico and abandoning their intention to migrate to the U.S., but by hunkering down and staying once they had run the gauntlet at the border and made it to their final destination.”
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