The Effects of Atomic Bombs on Hiroshima and Nagasaki

A cold and largely unfeeling assessment of the impact of the atomic bombs in Japan.

This jaw-dropping report was compiled by The United States Strategic Bombing Survey and published by the Government Printing Office in 1946. Its contents provide a matter-of-fact overview of the terrible effects of the two atomic bombs dropped on the Japanese cities of Hiroshima and Nagasaki on August 6th and August 9th, 1945. The Strategic Bombing Survey was organized in 1944 “to conduct an impartial and expert study of the effects of our aerial attacks on Germany, to be used in connection with air attacks on Japan” [pg. III] but its mission was modified by President Truman the week following the bombings to include an assessment of the new nuclear weapons.

The results, outlined in this report, almost boggle the mind. The 46 pages include summaries of the damage (human and property), photographs, an operational description of the bomb, commentary on the efficacy vs. traditional weapons, and recommendations for defense in the event of a nuclear war. One notable excerpt reads “The most striking result of the atomic bombs was the great number of casualties…most of the immediate casualties did not differ from those caused by incendiary or high-explosive raids. The outstanding difference was the presence of radiation effects, which became unmistakable about a week or so after the bombing.” Casualty estimates are provided at between 140,000 and 160,000 (dead and injured) for Hiroshima and around 80,000 in total for Nagasaki, though the survey admits other estimates are much higher – exceeding 250,000 in total.

Perhaps the most impactful elements are the two large folding maps affixed to the back of the report. The first, approximately 18.5″ x 18.5″, shows the extent of the fire and the limits of the blast damage around Hiroshima. Concentric circles in 1000 ft. increments radiate from Ground Zero, showing structural damage across a diameter of just over 4 miles. The second map is much larger, at approximately 47.5″ x 24″. Several different colors highlight the various levels of damage across Nagasaki, extending up to 16,000 ft (over 3 miles) from Ground Zero. Numerous locations of interest such as schools, hospitals, and military installations are labeled, reflecting the broad swath of destruction endured by the residents, regardless of military affiliation.

Source: Truman Library;