In the years 1803-5 Napoleon Bonaparte built 4 new harbours on his channel coast and assembled enough landing craft to put an army of over 165,000 men ashore on English beaches. Was this threat to Britain really serious and should we dismiss it as pure Bluff? Why was it never revived after Bonaparte’s continental wars against the Russians, Austrians and Prussians? What did the English do about defending themselves? This book, originally published in 1973 tackles these questions. It shows why Bonaparte’s flotilla was no Bluff but something the British were right to take seriously and also how their preparations to defend the beaches within reach of its bases made a revival of the flotilla after 1807 pointless. Though recognising the importance of Trafalgar the book rejects the fallacy that this victory ended Britain’s danger. The book covers the background of the war, Britain’s defence organisation, the Royal Navy’s tasks, Bonaparte’s preparations and how the British made ready to meet him.