Testimony of Mochitsura Hashimoto:
During his testimony, the US Navy questioned Hashimoto specifically:
Q. What kind of torpedoes did you fire?
A. (As given by interpreter Commander Bromley) Type 95 torpedoes, propelled by oxygen.
Q. Why did you not use KAITENS?
A. (As given by interpreter Commander Bromley) KAITENS weren’t used, first, because he was delayed in determining the type of target; secondly, because it was night; and thirdly, because torpedoes were considered to be sufficient. [11]
Not only does this testimony refute Dietrichs' claim as to the type of torpedo used by I-58 during the attack, but also proves that the subject of any use of Kaiten was indeed addressed during the trial of McVay.
The US Navy knew about the IJN's use of Kaiten both prior to and after the sinking of the USS Indianapolis.
In fact, the IJN Submarine I-53 had engaged a convoy protected by the USS Underhill ( DE-682) six days earlier on July 24, 1945, using a number of Kaiten.
I can find no evidence to substantiate Dietrich's claim that US Intelligence sources considered Japanese Kamikaze to be of "occult origin".