Page 70 - Unit 731 Testimony

powered and snorkel-equipped, so that its combustion engines could run
even while the boat was submerged. This characteristic enabled it to use
one of its two engines for propulsion, while it charged its batteries with the

other. At sixteen knots on the surface, it had a normal range of thirty-one
thousand nautical miles. Its range could be extended by filling the ballast
tanks with fuel oil instead of water. Filling the ballast tanks would, of
course, mean that the sub could not surface until after a sufficient amount of
fuel had been consumed, but Allied air and naval presence in the Pacific in
the early part of 1945 would make submerged travel prudent at any rate.
Reaching the American mainland seemed to be no problem, at least as far

as technology was concerned.
All discussion of the ultra-secret plan, first proposed toward the end of
December 1944, was confined to a special tactical room set aside at the
headquarters of the Naval General Staff in Hibiya, Tokyo. There were two

main drawbacks to conducting this operation as a purely naval venture. One
was a lack of data regarding the intended pathogens. The other was a lack
of the pathogens themselves. For this, the nation's highest authority on
biological warfare was called in, and Ishii became special advisor to the top
army man in the project, Colonel Hattori Takushiro. One might imagine
Ishii's anticipation as he envisioned American high-density population
centers filled with agony, with citizens turning to blackened corpses. It

would be a larger-scale success of— indeed a capstone to—his attacks on
Chinese cities and villages.
The plan was initiated as a joint army-navy project under the code

name "Operation PX." It called for the sub to approach the American shore,
then launch its planes and spread plague, cholera, and perhaps other
pathogens from the air. The submarine crews would run ashore carrying
germs. The entire attack was planned as a suicide mission.
The project moved forward from a foundation of biological warfare

intelligence provided by Ishii and Unit 731, and the plan was finalized on
March 26, 1945. Then, at the last moment, General Umezu Yoshijiro, Chief
of the General Staff, stepped in and ordered the plan scrapped. He reasoned
that "if bacteriological warfare is conducted, it will grow from the
dimension of war between Japan and America to an endless battle of

humanity against bacteria. Japan will earn the derision of the world."