In its eighty-year history, the international airline industry has been funded by aircraft manufacturers, shipping companies, banks and starry-eyed entrepreneurs, but by far the largest and most consistent source of support has been national governments; airlines, to a degree unmatched by any other transport mode, are children of the state. The reason for this close relationship is that air transport has had a political importance independent of its commercial possibilities. Three prominent features have virtually guaranteed that the state takes an interest in airline activities. First, international air transport, in contrast to transport by land or sea, intrudes without hindrance into a nation's hinterland – enters, in the jargon of the trade, its ‘air space’ – and therefore airline operations have always had strategic implications. Second, because airlines rely on the most advanced technology in modern manufacturing, the state, owing to techno-nationalistic concerns, is highly prone to interfere in their management and aircraft procurement decisions. Third, there is the question of prestige. The major international airlines which were formed in the 1920s and early 1930s, i.e. KLM, Sabena, Imperial Airways, Deutsche Lufthansa, Pan American Airways, Swissair and Air France, were ‘flag-carriers’.