In 1908, the motoring journalist R. P. Hearne published Aerial Warfare, the first book on the subject to reach an audience beyond military strategists. Enormous advances in aviation resulted in the publication of this substantially revised edition in 1910. At a time of intense European military rivalry, the book highlighted differences in the way countries were adopting new aerial technology. Hearne makes the assumption that conflict with Germany at some point is inevitable, and identifies the airship as 'practically an invisible enemy'. At this point Germany had ten airships compared to...