THE Nelson Mandela who is about to return to South Africa after his triumphant European and North American tour is a different figure from the man who embarked on that trip some weeks ago. His stature as a leader in the battle against apartheid already was large, but now it towers. In each country he visited Mr. Mandela has been treated, in all ways but strict protocol, like a head of state. He has become a world personage, and his cause has been shown to have strong international support. Mandela's added prestige will carry a lot of weight in further negotiations with Pretoria. In the words of one observer, the South African government now finds itself with a ``Gandhi-like figure to deal with.''
That could be nettlesome in some respects for the government of Prime Minister Frederik de Klerk, but Mandela's raised stature actually benefits the government as well as the black-liberation movement. In Mr. De Klerk's brave efforts to dismantle apartheid and achieve radical political reform, it should be more palatable to whites that their president is negotiating with a black leader of Mandela's world standing than with a fatigues-clad guerrilla chieftain.
Yet Mandela returns to a country roiled by new outbreaks of strife. White right-wing extremists have conducted a spate of terrorist bombings, including the office of the newspaper that disclosed an assassination plot against De Klerk and Mandela.
Meanwhile, divisions among black groups have been widened, as the African National Congress and affiliated organizations have sought to isolate and discredit other centers of black power.
De Klerk and Mandela will have to find a path through this minefield of white/white and black/black divisiveness. De Klerk must deal with the right-wing terrorism without further alienating other white conservatives.
Mandela's task may be even trickier. He and his colleagues must devise a political mechanism whereby all blacks will feel bound by the settlement eventually worked out with the government, yet which allows the expression of black pluralism. The preservation of healthy black political diversity is important, for it assuages white fears of ultimately being submerged in a one-party black state.
The democracies that Mandela visited can do more than just burnish his image. South Africa has a crying need for new political ideas, even a new political nomenclature freed of stereotypes and preconceptions. Let economic sanctions remain for now; but new thinking about democracy should flow freely into South Africa. It's time to widen the contacts with South Africa that will stimulate exchanges of ideas.