Under an obscure pre-WWII ruling by the agency that is now the FCC... "No information may be encoded or transmitted over PUBLIC or PRIVATE forms of telephony or radio with the exception of those agencies involved in the National Security" a further designation goes on to say "with the exception of the MORSE system of 'transmittal', any communication that is not interpretable by the human ear is forbidden and unlawful."
As a liscenced ham (amature radio operator), kb6wct, I can assure you that the FCC allows transmissions other than phone, and morse code. Here are just a few -- rtty, ascii, spread spectrum, fax, sstv, and ntsc video. Hams can SEND all of these over the radio. There are still other information transmission systems in use by comercial interests. However, the FCC does in fact dissallow hams from transmitting in "any code or cypher with intent to obscure the content of the message." This allows all cryptographic authentication systems, but not encryption. j'