The Kaiser's U-boat assault on America

The book is a well-researched history of Germany's First World War submarine gamble. Its account of U-53 off Nantucket shows how prize rules, neutral observers, merchant shipping, and American destroyers could create a dangerous incident without an immediate battle. The rules and choices surrounding the encounter continued to influence later maritime warfare and law. A later section follows Woodrow Wilson's response and shows how unrestricted submarine warfare narrowed the space for diplomacy before the United States entered the war.