The attack took place in the declared maritime war-zone around the UK, three months after unrestricted submarine warfare against the ships of the United Kingdom had been announced by Germany following the Allied powers' implementation of a naval blockade against it and the other Central Powers.
The passengers had been notified before departing New York of the general danger of voyaging into the area in a British ship, but the attack itself came without warning. After the torpedo struck, a second explosion occurred inside the ship, which then sank in only 18 minutes. It also contributed to the American entry into the War two years later; images of the stricken liner were used heavily in US propaganda and military recruiting campaigns. The contemporary investigations in both the United Kingdom and the United States into the precise causes of the ship's loss were obstructed by the needs of wartime secrecy and a propaganda campaign to ensure all blame fell upon Germany.
When Lusitania was built, her construction and operating expenses were subsidized by the British government, with the provision that she could be converted to an Armed Merchant Cruiser if need be. They were also very distinctive; so smaller liners were used as transports instead. Lusitania remained on reserve in the official AMC list and was listed as an auxiliary cruiser in the edition of Jane's All the World's Fighting Ships , along with Mauretania.
At the outbreak of hostilities, fears for the safety of Lusitania and other great liners ran high. During the ship's first eastbound crossing after the war started, she was painted in a drab grey colour scheme in an attempt to mask her identity and make her more difficult to detect visually. When it turned out that the German Navy was kept in check by the Royal Navy , and their commerce threat almost entirely evaporated, it very soon seemed that the Atlantic was safe for ships like Lusitania , if the bookings justified the expense of keeping them in service.
Many of the large liners were laid up over the autumn and winter of β, in part due to falling demand for passenger travel across the Atlantic, and in part to protect them from damage due to mines or other dangers. Among the most recognizable of these liners, some were eventually used as troop transports, while others became hospital ships. Lusitania remained in commercial service; although bookings aboard her were by no means strong during that autumn and winter, demand was strong enough to keep her in civilian service.
