There was no physical barrier between the U.S. and Mexico for decades -- until one critical battle at the border changed it all.

Nogales, a city of roughly 20,000 residents on the U.S.-Mexico border, has long relied on cross-border shoppers to support its local economy.

NOGALES, AZ — Mexico is Arizona's largest trading partner - and perhaps there is no other city in State 48 where that is more apparent than in Nogales. Last year alone, according to the Greater ...