Although Helen Zille has apologised for saying the legacy of colonialism was not all bad, one of the more delightful ironies of our politics is that her party and its leader will soon be participating in a parliamentary vote of no-confidence against President Jacob Zuma using a section of the Constitution copied from the imperial parliament in Westminster.

The idea that the head of the executive branch of government may remain in office only for as long as he or she retains the confidence of the legislature is a British import. It is given explicit force by Section 102 (2) of our 1996 constitution.

Nor is this the only principle that arrived on these shores during the colonial era. Colonial administrators did many terrible things in South Africa and elsewhere. But they also brought with them some of the founding values of our democracy. These include the principle of equality before the law and the notion of human rights. The very idea of the rule of law is part of our heritage, as is the idea that those who rule are also subject to the law. These date back to Magna Carta, signed by King John in 1215.

Arguably, the principle of equality before the law dates back to Christ himself. And the idea that a society should be governed by law dates back to Moses. Roman roads, Roman conquest, and the early church helped bring these values from the Middle East to Europe, and thence, courtesy of European navies, to parts of the world that the Europeans colonised.

Often these values were violated on a colossal scale by colonial administrators and other settlers in pursuit of power or profit or racial purity. Boers and black people were subject to barbarous treatment by the British. But missionaries fought against colonial administrators. So did liberal politicians, journalists, lawyers, and others. When courts tried to uphold the liberal principles of both Roman-Dutch law and the English common law which we inherited, they were thwarted by legislation that counteracted their decisions.

Nevertheless, part of the history of South Africa is that eventually the liberal values survived strongly enough to be incorporated into the constitution under which we are governed today.

A few months ago Ms Zille quoted Nelson Mandela as having said that South Africa’s understanding of the rule of law was part of our colonial heritage. Marian Tupy of the Cato Institute in Washington recalled that a one-time Indian prime minister, Manmohan Singh, said that the judiciary and legal system were among the great institutions derived from British-Indian administration.

To deny all this is to re-write history. It must not be allowed to succeed. This is not merely a question of recording and recognising a complex set of events, ideas, and participants. There is more to it. As George Orwell warned, “who controls the past, controls the future”.

Let us connect the dots in this unfolding narrative. Apartheid was a crime against humanity. Colonialism was just as wicked. It was brought here by white settlers. So whites are guilty of crimes against humanity. They have been at it since Jan van Riebeeck arrived.

Only whites can be racists. “Whiteness” is the mark of Cain. Whites stole all the land. The economy is in the grip of white monopoly capitalism. Whatever white people have achieved, whatever they own, is the result of criminality. Dispossession is therefore no more than their just deserts.

Some will say it is paranoid thus to connect the dots. But stigmatisation is one of the most powerful weapons in politics, which itself relies on propaganda. And it would be foolish to deny the growing tendency to stigmatise whites. It is a pity that the Democratic Alliance and their leader, in their determination to humiliate Ms Zille, have joined the African National Congress and various journalists in this malevolent enterprise.

* John Kane-Berman is a policy fellow at the IRR, a think-tank that promotes political and economic freedom. His memoirs, Between Two Fires – Holding the Liberal Centre in South African Politics, were recently published by Jonathan Ball.