While many great and extended conflicts involving the use of the sea have been fought over the past two thousand years, the three most notable in modern times were undoubtedly those struggles for global mastery in the years 1793–1815, 1914–18 and 1939–45. Each of these conflicts has produced a plethora of detailed works upon aspects of the war in question, but the profession has avoided making a comparative study of them to draw broader conclusions about the influence of sea power in the modern world. This chapter makes an attempt to do that, and with a particular interest in examining why the exercise of naval force during the second of the three conflicts is generally regarded as having had much less effectiveness than in the other two. Examining why naval power in 1914–18 had much less ‘influence’ than its pre-war advocates hoped might then help us to a better understanding of the limitations of naval force as well as of its positive capabilities. Above all, the essay is interested in the changing contexts in which sea power had to operate over these one hundred and fifty years of what one scholar nicely termed ‘the influence of History upon Sea Power’.

This is a lengthy argument, and so the structure of the essay below has been divided, rather obviously, into wartime and peacetime sections. Since the great naval struggle for mastery between 1793 and 1815 is generally regarded as the apotheosis of sea power in action, no detailed account is offered below of the many great battles that took place within those years, or of where British diplomacy and naval influence successfully marched hand in hand, as in the Baltic, or of the campaigns in the Eastern Seas. What seemed more important was to produce a reasonably brief structural analysis of why it was that sea power played such a prominent role in a struggle for the mastery of Europe that in the final analysis obviously had to be settled by military victory over Napoleon on land.