Well, the carriers were at sea and not a one was damaged. I believe several someones knew a lot. Unfortunately the ones in the path of the attack knew nothing until too late, and didn’t know it from our side
My dad was in the code room. I was young when he spoke of it, but as I recall he spoke of an undelivered message that sat in a mail slot for three days. My impression from him was the information in that note was definitive, and that it was not normal for it to be just left there like that. We knew everything we needed to know to defend ourselves and didn’t. That’s who FDR has been to me my whole life.