There are a variety of reasons why the top three Japanese makers have expanded their North American operations. For one, it lowers costs. For another, it increases automakers' flexibility to shift production, reducing potential logistical and quality issues.
According to industry watchers, Nissan and its competitors were also motivated to act following the major earthquake and tsunami that struck Japan in March 2011, all but shutting down the country's auto industry for months.
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Meanwhile, key production decisions were made earlier in the decade when the value of the yen rose to historic highs, and "it was not profitable to assemble vehicles in Japan," said David Sullivan, a senior automotive analyst with AutoPacific.
But it's not just the U.S. that's seeing a boom. Sullivan said Mexico's automotive production base "is on fire," noting that virtually every major global auto manufacturer is either operating, or setting up production, in the country. Mexico not only has a low cost base but is in an ideal location to supply both North and South America.
Although several external factors contributed to the shift toward North America, it's not expected to be a temporary trend. Between Mexico, Canada and the U.S., industry analysts have said they expect to see even more production shift to the region in the years ahead.
"Stability, exchange rates, and [other factors] mean we'll continue to see a shift," Sullivan said.