A recent lawsuit filed by former crew members and relatives of deceased crew members of fishing boats operating near the area where the United States conducted a series of nuclear weapons tests in the Pacific in 1954 — seeking compensation from the Japanese government over its questionable behavior at the time and in subsequent years — carries historical significance. More than six decades after the hydrogen bomb tests at Bikini Atoll in the Marshall Islands, beginning with a test explosion code-named Castle Bravo on March 1, 1954, the lawsuit will help shed fresh light not only on the scope of radiation exposure for Japanese fishermen but also on whether the Japanese and U.S. governments acted properly to deal with the consequences of the fallout from the tests.

Even before the court proceedings begin, the omission on the part of the Japanese government seems clear — its failure to properly examine and keep track of the potential damage to the fishermen's health and nondisclosure for decades of the records of their radiation exposure.

In connection with the 15-megaton Castle Bravo test, which was over 1,000 times more powerful than the atomic bomb dropped on Hiroshima on Aug. 6, 1945, the tragedy of the tuna trawler Fukuryu Maru No. 5, also known as the Lucky Dragon, is widely known. The fallout from the test fell onto the vessel for a few hours, causing its 23 crew members to suffer nausea. By the time they returned to their home port of Yaizu, Shizuoka Prefecture, two weeks later, they had developed serious symptoms of radiation sickness, and the radio operator, Aikichi Kuboyama, died six months later. The Fukuryu Maru incident sowed the seed for civic anti-nuclear movements in Japan.