More than 13,000 Conversos were put on trial during the first 12 years of the Spanish Inquisition. Hoping to eliminate ties between the Jewish community and Conversos, the Jews of Spain were expelled in 1492 ..
A second reason, specifically for using Morse Code during the Second World War, was encoding... Nowadays equipment exists to take an outgoing radio signal and automatically encrypt the data or voices during transmission, this is 'on-line' encryption...
Interestingly, in World War 2, squirrel was used as a shibboleth by the English to detect Germans, and EichhÃ¶rnchen, the German word for squirrel, was used as a shibboleth to detect non-Germans.