A rusty 12-foot fence is all that separates the United States from Mexico in Nogales, Ariz. The barrier traces up and down the surrounding hills from east to west, marking a flimsy separation and an ironic separation in this city of 40,000, where there are 12 million border crossings each year. Residents, commerce and culture go back and forth daily between Arizona and the Mexican state of Sonora. Like much of southern Arizona, Nogales' economic survival depends on Mexican tourists and consumers, who spend nearly $4 billion in Arizona each year. On a typical day in Nogales, the population ... Read More