In the 14 years since the dawn of black majority rule, inhabitants of South Africa’s townships have exhibited immense patience. The escalating violence against immigrants around Johannesburg should serve as a warning to South Africa’s rulers that this patience has an end.

In just over a week some 22 people from Zimbabwe, Malawi, Mozambique and other African countries have been lynched. Hundreds more have been maimed by mobs incensed at rising crime and unemployment that they blame on immigrants among them. Some of the victims are fleeing back to Zimbabwe – a measure of the traumatic nature of their experience but also of the strength of frustration and anger in South Africa’s underclass.