The Sussex pledge was a pledge made by the Germans during the world war 1. to the united states of America that they wouldn't sink or torpedo any passenger or merchant ship unless the Merchant ship is armed.
The united states of America was neutral in the world war 1 prior to the agreement but later joined the world war 1 by declaring war on Germany in 1917. when Germany broke the agreement by sinking a French passenger ship ( resumption of unrestricted marine warfare) by the Germans.
The Germans broke the agreement because they were anticipating that they would defeat Britain before America and the French would join the war.
Explanation: The Sussex was a french passenger ship which was torpedoed by Germany for seemingly no reason, and 50 people died because of it, and Woodrow Wilson made Germany sign a pledge not to torpedo any more passenger ships, which Germany broke a few months before america entered war
In addition to eight appearances on Saturday Night Live between 1981 and 1985, Anderson had a recurring guest role as con man Harry "The Hat" Gittes on Cheers. He toured extensively as a magician, and did several magic/comedy shows for broadcast, including Harry Anderson's Sideshow