Telsa is without doubt one of the greatest scientists to have ever lived. He was years ahead of his contemporaries and the establishment did all that they could to silence and discredit him.
Ask most people today what they know about Telsa and you might get a reply like this:
'it's is a car that Elon Musk built'
Sad but true!
Personally, I think that the FBI retained the documents that they didn't want to see the light of day.
I think some good books about Tesla need to be written for kids as well as teachers.