This article by Ken Keable appeared in the Guardian "Comment is free" section on 24th August 2012.

After Nelson Mandela and other leaders of the African National Congress were jailed in 1964, almost all ANC members who were not in prison or under severe internal restriction had to go into exile to evade arrest and torture.

Once out of immediate danger, they then had another problem: how could they continue the struggle against the apartheid regime? How could they show the people that the ANC was not defeated? The ANC's four-man London leadership found an answer. They began recruiting young, white, non-South African men and women, unknown to the regime, who could enter South Africa without arousing suspicion. I was one of those London recruits.

Ronnie Kasrils (later to become head of military intelligence forUmkhonto we Sizwe, the ANC's armed wing, and then a minister under Nelson Mandela and Thabo Mbeki) enrolled at the London School of Economics LSE, where he quickly found suitable people among the leftwing students, including members of the IS, forerunner of the Socialist Workers' Party. However, the main source was the Young Communist League. Born in 1945 into a communist family, I was recruited in this way.

I flew to Johannesburg in 1968, smuggling in and posting about 1,200 letters addressed to the Indian community. In 1970, I went to Durban, with my friend Pete Smith. At the "non-white" bus and railway station, in the rush hour, we planted several "exploding bucket" leaflet bombs, harmless devices that blasted ANC leaflets high into the air. We also arranged a street broadcast, using a cassette player and an amplifier, broadcasting ANC speeches and freedom songs.

We later discovered that we were not the only ones – the ANC's London recruits did the same thing simultaneously in five cities. They did similar things annually from 1967-71, helping the ANC to rebuild its internal structures. They unfurled banners, smuggled weapons, helped ANC fighters to enter the country, carried messages to individuals and did reconnaissance. Three – Sean Hosey, Alex Moumbaris and his French wife Marie-José – were arrested and tortured. The authorities had no idea that it was "London calling".

This was at a time when most major British companies had subsidiaries in South Africa, operating its racist policies and benefitting from its cheap labour. British banks were investing in South Africa. Margaret Thatcher famously described the ANC as a terrorist organisation and gave the regime diplomatic protection.

At the United Nations, our government vetoed the expulsion of South Africa, overruling the general assembly. These are the facts that, in my view, justify what we London recruits did. It is an inspiring, largely untold story of youthful idealism, international solidarity and self-sacrifice of which Britain can be proud.

In June this year, a small group of veterans of the campaign toured South Africa. We made the point that the defeat of apartheid had struck a powerful blow against racism all round the world but especially in Britain, amply repaying us for our efforts. We had shown not only that international solidarity works, but also that it helps to make the world better for everyone.

Two of the recruits had a narrow escape. When they went to Durban in 1971, Graeme Whyte and Denis Walshe, being working-class lads, were not familiar with hotels. To prepare their leaflet bombs, they locked the door and got to work, opening their false-bottomed suitcases. Soon the room was full of plastic buckets (purchased locally), wires, time switches and piles of ANC leaflets – thousands of them. In walked a black woman, about the same age as them, to clean the room. She had her own pass key, of course.

After quickly taking in the extraordinary scene, she left. What were they to do? After considering their options, they found her at the linen cupboard, brought her back, sat her down and handed her a leaflet. She read it carefully and said: "You are fighting for us." She didn't betray them.

This interesting report by the BBC, about the truck used for the "Secret Safari" arms smuggling operation, somehow manages to avoid mentioning that the drivers and tour guides were all white non-South Africans, mostly British people, acting in solidarity with the ANC.

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