ABSTRACT
Actual experience in the First World War provided little incontrovertible evidence in support of Halford John Mackinder's thesis. Indeed two prominent advocates of aviation felt that the conflict's greatest single lesson was that: In the future a nation which dominates the aerial highways will dominate also those of the land and sea. Air power's introduction and maturation helped make warfare more a matter of zones than fronts. This effect was particularly pronounced in the maritime environment, where, by means of not only aircraft but also submarines, which were refined alongside them, the third dimension could be exploited to a degree that was simply not possible in operations confined to land masses. During the First World War command of the air yielded mixed and marginal results. Whereas it helped make land offensives that much more viable, in maritime settings aviation's accomplishments were largely less tangible.
