ANC secretary general
"You have made an assumption that if you decide to leave the ANC, the ANC will become static," Mantashe told Police and Prisons Civil Rights Union (Popcru) members on Wednesday at their second national political school in Benoni, east of Johannesburg.
"[However] you will have an ANC that will grow more and more conservative and once it is more conservative, it will be brutal on the working class."
Mantashe said working-class organisations, such as the unions and the South African Communist Party, influenced the standing of the ANC.
The liberation movement, led by the ANC, was a multi-class revolution and if the working class decide not to support the party other classes will take over the space and shift it.
"If you think it's neo-liberal now … You will push it [the ANC] to the right," he said.
Mantashe urged union members to engage with Cabinet ministers, especially those who were former union members.
Class struggle
He used Basic Education Minister Angie Motshekga and the South African Democratic Teachers' Union (Sadtu) as an example.
Motshekga is a former Sadtu member and now that she is a minister, the union is fighting her.
"I looked at Cabinet and I established that a big chunk of it can be traced back to the trade unions … but they [unions] cannot talk to their former members."
Mantashe was speaking under the theme forms and content of the class struggle.
Mantashe also touched on the problems facing Cosatu, saying the federation needs to focus on its principles.
"Once you close your eyes to those fundamental principles you are going to see the battles that are running now. Those battles are a function of many things."
Mantashe said one of those things is the development of personalities in Cosatu. "When you begin to worship individuals then you are going to kill the thing [Cosatu]."
Cosatu is divided following allegations of rape against general secretary Zwelinzima Vavi and his subsequent suspension.
Special leave
Cosatu announced on Thursday that Vavi has been put on special leave pending the outcome of a disciplinary hearing into an affair he had with a junior employee.
Vavi vowed on Friday to challenge his suspension. A junior Cosatu employee accused Vavi last month of rape.
He admitted to having a consensual affair with her. The woman subsequently withdrew the sexual harassment complaint against him.
Cosatu affiliates, such as the National Union of Metalworkers of South African (Numsa) and the Food and Allied Workers Union (Fawu) have backed Vavi.
The unions have called for Cosatu president Sidumo Dlamini to be removed from his position after he said Cosatu had been damaged.
They claim the special central executive committee meeting that suspended Vavi was not properly constituted.
Numsa, Cosatu's biggest affiliate, said it had lost faith in Dlamini and that he was not representing all Cosatu affiliates.
Mantashe on Wednesday said Cosatu needs to appreciate the fundamental principles and focus on its responsibility to workers.
"You gave power to general secretaries and killed worker control," he said. "Once you do that, you tamper with the content and nature of the trade [union] movement." – Sapa