Project 4.1
In 1994, a 1953 "Castle Bravo" program prospectus was found which included reference to Project 4.1 apparently written before the "Bravo" shot had occurred. The U.S. government responded that someone had gone back into the project list after the "Bravo" test to insert Project 4.1; thus, according to the U.S. government, the acts were not premeditated. All other U.S. documents point to Project 4.1 having been established after the "Bravo" test—most sources point to its having been organized on March 7, 1954. The final Project 4.1 report began in its preface with the statement that "Operation CASTLE did not include a biomedical program" (it mentions this in discussing the ad hoc nature by which the project personnel were assembled). All official and mainstream historical accounts of the "Bravo" test indicate that its high level of fallout was a result of a miscalculation in relation to its design and was not deliberate (see the Castle Bravo article for more information on the alleged accident).
Radiophobia
This incident, due to the era of secrecy around nuclear weapons, created widespread fear of uncontrolled and unpredictable nuclear weapons, and also of radioactively contaminated fish affecting the Japanese food supply. With the publication of Joseph Rotblat's findings that the contamination caused by the fallout from the Castle Bravo test was nearly a thousand times greater than that stated officially, outcry in Japan reached such a level that the incident was dubbed by some as "a second Hiroshima". To prevent the subsequent strong anti-nuclear movement from turning into an anti-American movement, the Japanese and U.S. governments agreed on compensation of 2 million dollars for the contaminated fishery, with the surviving 22 crew men receiving about ¥ 2 million each, ($5,556 in 1954, $ in 2022)