According to the 1989 Asahi Nenkan, there were 14,400 activist members of the "extreme left wing" organized into five major "currents" (ryū) and twenty-seven or twenty-eight different factions.
In the early 1970s, radical groups and normally conservative farmers formed a highly unusual alliance to oppose expropriation of the latter's land for the airport's construction.
Formed in 1969, it was responsible for, among other acts, the hijacking of a domestic Japan Airlines jet to Pyongyang in 1970[citation needed] and the 1972 Lod Airport massacre.
Following heavy criticism at home and abroad for the government's "caving in" to terrorists' demands[citation needed], the authorities announced their intention to recall and reissue approximately 5.6 million valid Japanese passports to make hijacking more difficult.
They tended to be fascinated with the macho charisma of blood, sweat, and steel, and they promoted (like many nonradical groups) traditional samurai values as the antidote to the spiritual ills of postwar Japan.
Their preference for violent direct action rather than words reflected the example of the militarist extremists of the 1930s and the heroic "men of strong will" of the late Tokugawa period of the 1850s and 1860s.
The modern right-wing extremists demanded an end to the postwar "system of dependence" on the United States, restoration of the emperor to his prewar, divine status, and repudiation of Article 9.
The ritual suicide of one of Japan's most prominent novelists, Yukio Mishima, following a failed attempt to initiate a rebellion among Self-Defense Forces units in November 1970, shocked and fascinated the public.
Mishima and his small private army, the Shield Society (Tatenokai), hoped that a rising of the Self-Defense Forces would inspire a nationwide affirmation of the old values and put an end to the postwar "age of languid peace."
Although right-wing extremists were also responsible for the assassination of socialist leader Inejiro Asanuma in 1960 and an attempt on the life of former prime minister Masayoshi Ōhira in 1978, most of them, unlike their prewar counterparts, largely kept to noisy street demonstrations, especially harassment campaigns aimed at conventions of the leftist Japan Teachers Union.
The Sekihotai also threatened to assassinate former Prime Minister Yasuhiro Nakasone for giving in to foreign pressure on such issues as the revision of textbook accounts of Japan's war record.
The enthronement ceremonies were considered likely targets for extremist groups on the left and the right who saw the mysticism surrounding the emperor as being overemphasized or excessively reduced respectively, but no serious incidents took place.