"When Nelson Mandela called Nigeria's hanging of Ken Saro Wiwa and eight fellow activists 'a heinous act' last weekend, he was sounding a call rarely heard in African politics," reports TIME's Andrew Purvis. Historically, few African leaders have taken it upon themselves to censure the reprehensible behavior of other heads of state. Mandela, however, has begun to match words with action. On his urging, Nigeria was suspended from a New Zealand Commonwealth meeting where the South African leader made the statement. Tuesday, South Africa's soccer federation barred Nigeria's team from playing in South Africa, and calls are mounting for the African National Congress to seek Nigeria's ouster from the Olympic Games as well as a boycott of Nigeria's crucial oil industry. But Purvis reports that South African officials may not want to take it that far. "Indeed, it is not clear how much of an effect censure from South Africa and a few other countries on the continent might have on the Nigerian regime," he says. "Still, South Africa's actions so far may be the beginning of a new era of self-censure in African politics."