The United States of America is often divided into different belts. The heavily religious South East holds the title of the “Bible Belt,” while the de-industrialising North East and Midwest, once known as the “Steel Belt,” is now designated as the “Rust Belt”. Whether it’s reflective of social trends, common economic features or similarities in climate, nearly every state in the union is part of some sort of belt.

But of all the belts that criss-cross the United Sates, one in particular seems to be in the midst of a resurgence: the Sun Belt.

Referring to the collection of states that compose the lower third of the US, stretching from North Carolina to southern California, the Sun Belt has seen some of the strongest population growth in the union. Between 2014 and 2015, the Sun Belt as a whole saw over 500,000 new residents arrive – most of its attributable to domestic migration. Of the ten fastest growing metro areas over the same period, all but two were located in the Sun Belt.

And so, many commentators have heralded the return of the Sun Belt. “With the economy healing,” notes Slate magazine, “Americans have started settling back into their old habits, moving off to warm suburbs in states like Florida and Texas.” CityLab has dubbed the Sun Belt 2015’s “population winner,” while the Brookings Institute has noted a “noticeable expansion of Sun Belt migration”.

AirCon and the Cold War

The idea that the Sun Belt composed a distinct region emerged initially in the late 1960s, courtesy of Republican Party strategist Kevin Phillips who, in The Emerging Republican Majority, noted the region’s growing electoral importance to his party. (Ironically, Republican strength in many Sun Belt states – North Carolina, New Mexico, Texas and Georgia — is now weakening due to the population growth and demographic change, set-off by the Sun Belt’s boom.)

Between 1940 and 1980, the Sun Belt saw its population grow by just over 112 percent; by way of comparison the combined North East and Mid West saw their population grow by just 41 percent. The US’ economic and demographic centre of gravity has gradually shifted south.

A number of factors drew Americans to the Sun Belt region. First, the creation of the interstate highway system under President Eisenhower opened up once isolated southern regions, particularly in the South West. At the same time, the invention of air conditioning made both the arid desert climate of the South West and humid heat of the South East more tolerable.

Related to this was the defence boom, as the Cold War resulted in a flurry of federal spending on the defence and technology industries. Writing in the 1980s, the political consultant and writer Richard S. Morris noted that states in the North East, with 45 percent of the US population, received 28 percent of national defence spending; the Sun Belt, at the time holding 38 percent of the nation’s population received almost half. The Pentagon, he quipped, was “a five-sided building that faces south”. The clustering of highly skilled and educated personal in the defence sector – as well as the large grants given to research universities – also boosted the civilian sector, leading to growth in areas like the Dallas-Fort Worth “Silicon Prairie”.

While the South West has been viewed as an ideal destinations for Americans to migrate to, the South East, at least since the end of Civil War, has been a place from which people escaped. From African-Americans moving to Chicago and Detroit, to white inhabitants of Appalachia crossing north of the Ohio River, the South East has been a place of outward migration.

Yet the Sun Belt’s post-war rise has seen this trend starting to reverse: for the first time in roughly a century, a combination of federal defence spending and business friendly policies meant that many south eastern states have shared in the inward migration.

What’s in a name

The name itself may have helped: rebranding the southern third of the US as the Sun Belt, Bruce J. Schulman notes in From Cotton Belt to Sunbelt, “offered the land of Dixie a fresh identity”.

Bradley R. Rice expanded on this theme in the 1990s. ”The South was known to be hot and muggy,” he wrote in his contribution to Raymond A. Mohl’s Searching for the Sunbelt: Historical Perspectives on a Region. “The Sun Belt was portrayed as sunny, mild and mechanically cool. The South was unsophisticated and backward; the Sun Belt was seen as cosmopolitan and forward looking.”

This image revamp boosted the region’s appeal as a place for both people and business to relocate. Whereas the old South East was seen as a place of “sharecroppers and lintheads”, the new name made it sound dynamic and high tech. “Yankee executives might balk at moving to the South, but they might seek to locate in the Sun Belt”.

This renewed image is still drawing people in today. While jokes may persist about the backwardness of the Southern US, and images of the racial horrors of its past still linger in the popular imagination, in the past 60 years the demographic and economic weight of the US has steadily continued to shift south. From North Carolina’s “Research Triangle” to the sprawling cities of Texas’ or the population magnet that is Atlanta, Americans are flocking to the Sun Belt in search of more affordable living and better job prospects.

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