After the WW II, various activities and movements advocating for peace have been started in Hiroshima, matching in the trend of their times.
The “lost decade”
The decade after the A-bombing (from 1945 to 1956 when a nationwide organization, Japan Confederation of A-and H-Bomb Sufferers Organizations [Nihon Hidankyo] was established) is referred as the “lost decade.” This is because A-bomb survivors were neither understood by society nor fully supported by government administrations during those years. However, even in this period, anti-nuclear and peace movement gradually developed in Hiroshima. Specifically, in 1952, the Asia Congress for World Federation was held and called for a ban on atomic weapons.

Bikini Atoll hydrogen-bomb incident drove the movements to action
In March 1954, the Japanese fishing boat Daigo Fukuryu Maru (Lucky Dragon No.5) was exposed to radiation from American hydrogen bomb tests at Bikini Atoll. Spurred on by the incident, movements against atomic and hydrogen bombs began across Japan; and the first World Conference against A & H Bombs was held in Hiroshima. Since then, movements in Hiroshima have taken leading roles in anti-nuclear and peace advocacy, and Hiroshima has consistently called for the abolition of nuclear weapons and relief for A-bomb survivors.

Split and diversification of the movement against atomic and hydrogen bombs
As the movement against atomic and hydrogen bombs in Japan was linked with the labor movement, initially, the movement had the support of many political parties. However, the conservative party withdrew its support due to a conflict of opinion between the political parties. Then, the peace movement split into three in the early 1960s, and was weakened even further.
Coincidentally, this led to the rise of new citizen movements. The movements split from political activities and set more concrete objectives to achieve. Citizens worked together to achieve these many objectives including asking the Japanese government to issue a white paper on atomic and hydrogen bombs, restoration of a precise map of the A-bombed area, preserving the A-bomb Dome, organizing atomic bomb exhibitions throughout Japan, and purchasing movie footage of Hiroshima and Nagasaki taken by the U.S. Military. The activities of these movements were actively broadcasted with the full support of the mass media.

Movement beyond the border
In the late 1970s, the movements expanded beyond Japanese borders. Signaturecollecting campaigns for the abolition of nuclear weapons increased in scale until they were held across the country; and 18 million and 23.7 million signatures were collected for the first and second UN Special Sessions of the General Assembly Devoted to Disarmament, respectively (SSD I in 1978 and SSD II in 1982, both held in New York). Citizens of Hiroshima visited the U.S. (500 participated in SSD I and 1300 participated in SSD II) to call for the abolition of nuclear weapons. Since then, citizens have had strong interest in diplomatic campaigns for nuclear disarmament, such as those held by the United Nations.

Issues following the enactment of the Atomic Bomb Survivors Support Law
A-bomb survivors have long continued to call for the abolition of nuclear weapons and for national indemnities. Tough there still remain some issues yet to be resolved, support measures for survivors have expanded through the 1995 enactment of the Atomic Bomb Survivor’s Support Law. Meanwhile, the challenge of the abolition of nuclear weapons remains to be overcome; and there are ongoing efforts to achieve it.