In We Shall Fight on the Beaches, Brian Lavery, Curator Emeritus of the National Maritime Museum, in Greenwich, and author of In Which They Served, Churchill Goes to War, and many other works on the Royal Navy and Britain at war, has produced a unique comparative history of British preparations to face the invasion threats posed by Napoleon in 1805 and by Hitler in 1940. 

Each of the thirteen chapters examines a different aspect of the problem. Chapters compare the political and economic situation in Britain in both periods, the civil and military leadership, social unity and popular support for the war, intelligence, enemy plans and capabilities, the geographic setting (in some ways the same, in others different), the regular armed forces, the militia and Home Guard, inter-service cooperation, and, of course, defense plans. 

Lavery concludes with a look at how the threat evaporated in both eras. In the case of Napoleon, it seems probable that there was no serious threat of an invasion. In that of Hitler, however, the threat was serious, but after the Battle of Britain, his attention was diverted elsewhere. To the treatment of the Hitlerite threat, "Opertion Sea Lion", Lavery adds an account a series of war-games conducted at Sandhurst in the early 1970s that involved play by British and German officers who had taken part in the original planning, the outcome of which strongly suggests that had the invasion taken place it would have failed disastrouly. 

A very good read for anyone interested in the Napoleonic Era, World War II, amphibious operations, and war-gaming.

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