Wischnewski earned the nickname "Ben Wisch" from West German Chancellor Willy Brandt due to his strong contacts in the Arab world and his engagements with the AlgerianNational Liberation Front (NLF). As a close confidant of Brandt's successor, Chancellor Helmut Schmidt, Wischnewski served as a special representative for negotiations during the Red Army Faction (RAF) kidnappings in the "German Autumn" of 1977. In the 1980s, he led negotiations for the release of hostages and facilitated peace talks in Latin America and the Middle East.
After the war, Wischnewski joined the SPD. He was employed by a metal-working company and from 1952 trained as an IG Metall union secretary. Upon the 1957 federal election, he became a member of the Bundestag parliament and also an SPD board member in the Cologne district. He was elected federal chairman of the party's Young Socialists youth organisation in 1959 and joined the SPD federal committee in 1970, from 1979 as deputy chairman. From 1961 to 1965 he also was an elected member of the European Parliament.
Because of his strong relations with Arab politicians since the days of the Algerian War, Wischnewski was nicknamed "Ben Wisch" by Chancellor Willy Brandt (later sometimes spoofed as "Ben Cash" because of his duty as the SPD federal treasurer). His efforts decisively improved the West German diplomatic relations with numerous Arab and African countries. Also, after the 1973 Chilean coup d'état, he played a vital role in rescuing German and European hostages.
Wischnewski became widely known internationally for his pivotal role in the negotiations during the "German Autumn" terrorist attacks of 1977. When West German business executive Hanns Martin Schleyer was kidnapped by the militant Red Army Faction (RAF) in September, Wischnewski followed the joint RAF and Popular Front for the Liberation of Palestine (PFLP) hijacking of Lufthansa Flight 181 to Mogadishu, Somalia, in October. During the hijacking, he engaged in diplomatic efforts with several Arabian governments on behalf of Federal Chancellor Helmut Schmidt and negotiated with the Somalia government. As a special representative of the West German Federal Government, he negotiated with local authorities at the airports where the plane landed, including in Mogadishu, where he successfully coordinated the West German GSG 9 counterterrorism unit's storming of the plane and rescue of 91 hostages. Three of the hijackers were killed, and the fourth survived her critical injuries.
