Taoka was
imprisoned for murder from 1937 to 1943 and assumed the role of
kumicho three years later, at the age of 33. As
World War II and the subsequent
occupation of Japan wound down, however, more national focus would be given onto the internal criminal syndicates. Consequently, severe police crackdowns and arrests would be constantly imminent, making it a high cost venture for relatively low profit. Taoka realized that the economic activities in the back alleys would quickly come to a dead end, and a suggestion from a friend made Taoka start a full-fledged port cargo handling business instead. In his time as boss, Taoka expanded the Yamaguchi-gumi from a small strikebreaking gang on the Kobe docks to the world's largest criminal syndicate, with over 10,000 members during its peak. Notoriously suspicious and wary of rival yakuza clans, he notably refused to join the
Kanto-kai, an inter-yakuza confederation in 1963. In 1972, following a period of tension between both gangs, Taoka forged an alliance between the Yamaguchi-gumi and the
Inagawa-kai at a
sakazuki ceremony at his home. Taoka survived a 1978 assassination attempt when he was shot in the back of the neck by a member of the
Matsuda-gumi (松田組), a rival gang to the Yamaguchi-gumi, during a limbo dance exhibition at a nightclub in
Kyoto. His attacker was found dead several weeks later in the woods near
Kobe. ==Death==