During the Battle for Okinawa most Marines are aware that the Japanese used Suicide (Hari Kari) planes against us. But there was more, they used Suicide Boats against us also. Inclosed is a picture of the suicide boats. Some boats had Ford and Chevrolet engines in them. They were not effective for lots of reasons, we had PT Boats and other types of patrol craft that kept them from being very effective, as soon as they began their run the PT boats were on them. There were problems with this idea on stopping the Hari Kari Boats also, some were armed with two depth charges, which went off at shallow depths which could cause damage to nearby ships and serious injury and death to American and Allied Personel.
Among other exciting things they intended to usâ€‹e against the Invasion Forces were Swimmers, that had explosives attached to themselves and could damage a ship, their purpose was to put explosives on the ships screw which would prevent the ship from moving but I saw ships screws turning from time to time which would make it difficult for a swimmer to attach anything to the screw.
And when we Arrived in Japan after they surrendered there were hundreds of tunnels dug into the hills with tracks coming from them where suicide boats could be launched (we could still see the tunnels when we went to Korea, stopping at Japan). The Invasion of Japan according to Naval Intelligence at the time, would cause nearly a million casualties (both American, Allied and Japanese).
Many of us that were preparing for the invasion of Japan, expected it to be our last day on Earth. Even a friend who was a Gunner on a B25, expected he wouldn't live through the invasion of Japan. All this information will be in books about our preparation of the Invasion of Japan but little thought will be given to the thousands of ships and thousands of men that were there, the thoughts and the letters that were not mailed because the writer lived through the Invasion.
GySgt. F. L. Rousseau, USMC Retired