Rubuta ci gaba ga wannan sakin layi - Dan jarida mai ra'ayin gurguzu Willi Eichler ya gaji Nelson a matsayin shugaban ISK bayan mutuwarsa. Eichler da Specht duka za su sanya hannu a cikin 1932 "Kira na gaggawa don haɗin kai" ("Dringender Appell für die Einheit") a cikin jaridar ISK ta hukuma, "Der Funke". Ya yi kira ga Jam'iyyar Social Democratic ta Jamus (SPD) da Jam'iyyar Kwaminis ta Jamus (KPD) don ƙirƙirar haɗin gwiwar hagu don hana Nazis. Bayan an ci Nazi a shekara ta 1945
, ISK ta haɗu da SPD tare da yarjejeniyar da aka cimma a ranar 10 ga Disamba, 1945, tsakanin shugaban ISK (Will Eichler) da shugaban SPD (Kurt Schumacher). Koyaya, ISK ya ci gaba da kasancewa mai himma a cikin juriya da Nazism. An kirkiro wani reshen ISK na Burtaniya (wanda ya kasance daga 1920s zuwa 1950s) a Burtaniya da ake kira Socialist Vanguard Group.