Jay M. Winter, Cambridge University, on The Lusitania

The Lusitania was sunk two weeks after gas warfare opened on the Western Front. It's another example of the way in which the character of the war changed in 1915. It isn't that it was the first time that civilians had been casualties. It's true, they had been casualties from early days in the war through the German invasion of Belgium and northern France. But once the German navy decided to interdict supplies going from North America to Britain and then from Britain to France, then any ship could conceivably be carrying munitions, because munitions meant almost anything. The Lusitania had civilians on board. It was clearly a ship that could have been a danger to the German war effort, and the German navy didn't want to take the risk. Any ship that could have carried munitions was a danger to Germany. The Lusitania was a danger to Germany. And that's why German sailors cheered when they heard of its sinking. They weren't more blood thirsty than anybody else. They believed that this was the way that the war, total war, had to be waged.

There is no way that the German war effort could be accomplished without civilian casualties. It's a change in the nature of the war. Most people on the Lusitania didn't believe it, but very shortly thereafter, they did. And, the way in which German forces waged that war was so important in generating a propaganda campaign of hatred: not of the German leadership, but of the German nation as a whole -- of everybody who stood behind the German flag and were responsible for those who were drowned in the Lusitania. [They] were responsible for war crimes that were generalized not as the responsibility of a handful of officers who gave the orders to sink the Lusitania, gave the orders to use poison gas, but the whole German nation. Now, this kind of generalized stereotyping we sometimes call racism. It was the case that there was the propaganda of racial hatred in the First World War generated by the new kinds of hostility, the new kinds of weapons, and the new and appalling levels of casualties that occurred in the First World War.

From interviews for the PBS series The Great War.