We do? I don't think so. Rather difficult to "break radio silence" when critical occillators are removed from all radios from ships in Kido Butai. Neat trick. It was part of the Japanese communication plan. Now...if you can explain to me why The Japanese would break radio silence before a impending attack on Pearl Harbor I would be please to hear it. Th radio traffic heard was standard maritime weather code used by commercial ships to transmit local weather conditions. Not even a code really. A kind shorthand for meteorolgists. RDF fixes on the transmission put it 1,100 miles behind Kido Butai. Toland made the mistake of asumming this was Kido Butai and failed to check the Lats and Longs. derived from the RDF intercepts. He came a cropper as a result. He went for the brass ring of History. " FDR Knew"..many have tried. Toland's attempt was particularly sad. He was an old man swinging for the fence.In his zeal, he lost the historian's natural skepticism and failed to take the elemental precautions to insure the integrity of his work. He failed to submit his book for peer review prior to publication. He could have saved himself a great deal of grief. After his book he was like a haunted spectre among his colleagues. They were soliticous, kind, and sheltering. When that happens a historin is done. It is like treating a horribly wounded colleague. Did FDR know?...He may have. Is there compelling evidence to support the assertion. No... Not yet. Is there lots of time worn speculation presented as fact? Tons of it.
Did you read Stinnett's book, published in 2000 and based on newly released documents? I thought he made a compelling and well-documented case, albeit without ever having gotten a sworn statement of guilt from FDR.
As I see it, the solution that would end public speculation about unknowns, murky links and circumstantial (though substantial) inferences is to release the remaining state secrets 50 or more years old, and that should include even the documents that go all the way back to WWI. History deserves better answers.
BTW, this is not to argue that the PDFs should be released to the Kean panel -- which would jeopardize our ability to produce sound intelligence estimates in our War on Terror -- if they were be subject to political potshots and second guessing.