Japanese, Chinese, and some Western scholars have over the past forty years studied exhaustively the history of Japan's BW program and the subsequent American cover-up. They have examined the mountains of BW-related documents that still exist in their respective countries. Serious journalists have written extensively on the subject.! The British tabloids resurrect Ishii and BW periodically. Television documentaries in Japan and in Great Britain in the 1970s and 1980s popularized the topic. In the mid-1980s, the widely viewed American television programs Sixty Minutes and 20/20 devoted segments of their programs to Japanese BW.2 And, finally, Japan's NHK Television aired a two-part documentary on Ishii and BW in April 1992.3
In spite of the extensive research conducted over nearly one half-century, and the periodic public discussions, nagging questions concerning Japanese BW remain unanswered. Some of the questions cannot be resolved because archival depositories containing sensitive material are still closed to scholars in Japan, the United States, Great Britain, China, and the former Soviet Union.4 It is safe to assume also that the depositories will remain closed to researchers for some time. Nevertheless, because BW is such a dangerous possibility, certain questions should be raised concerning past and present research in this field, and tentative answers should be considered.