The defence sector provided a massive fillip to the economy of the Sun Belt states during World War II, sustained subsequently by continued high military spending during the cold war. Defence spawned a host of ancillary industries, attracted by the availability of relatively cheap, skilled and non-unionized labour. Electronics, chemicals and aerospace all boomed post-war, while the productivity of the agricultural economy was revitalized by the green revolution in farming technology. In Texas and Oklahoma, oil acted as a further growth accelerant. A key factor in American industry’s southward realignment was the post-war availability of cheap and effective air-conditioning, transforming both workplace and home environments. Coupled with abundant employment, population boomed, both from high birth rates and arrival of working age migrants from the declining Rust Belt and from Latin America, supplemented by sun-seeking retirees. The rise of the ‘New South’ was reflected politically: from 1964–80, all elected presidents hailed from the Sun Belt.