SUSSEX CASE. On 24 March 1916, a German submarine attacked the English Channel steamer Sussex. The United States, regarding this action as a violation of the pledge given by the German government in the 1915 Arabic case, responded that unless Germany stopped using submarines against passenger and freight vessels, it would sever diplomatic relations. The German government gave the necessary assurances, but with the qualification that the United States should require Great Britain to abandon the blockade of Germany. The United States refused to accept the German qualification. Consequently, when Germany renewed submarine warfare on 1 February 1917, the United States severed relations.
Safford, Jeffrey J. Wilsonian Maritime Diplomacy, 1913–1921. New Brunswick, NJ: Rutgers University Press, 1978.
Terraine, John. The U-boat Wars, 1916–1945. New York: Putnam, 1989.
Bernadotte E.Schmitt/a. e.