In "Dead Wake: The Last Crossing of the Lusitania," Erik Larson discusses a critical moment when Germany publicly declared the waters surrounding the British Isles as an "area of war." This announcement marked a significant escalation in maritime conflict, indicating that any enemy vessels, including civilian ships, were at risk of being targeted without prior warning.

This proclamation heightened tensions during World War I and reflected the ruthless nature of naval warfare at the time. The implications for passenger ships like the Lusitania were dire, as it became increasingly perilous for civilians to travel across these dangerous waters.