THE Party slogan in Orwell's Nineteen Eighty-four has renewed relevance in debates over the preservation or toppling of statues in the aftermath of the BLM demonstrations. 'Who controls the past controls the future; who controls the present controls the past.' Most commonly, this re-arrangement of a cityscape follows regime change, which invariably requires not just control of the future but also a rewriting of history. The icons of the past must go.

This rearrangement has been underway for some time in many countries. Unnoticed by the rest of the world, Samoa pulled down the Court House which has stood for over a century on the Beach Road in Apia, the nation's capital. It was a grand building in its own way, tidily designed with a balcony running round the upper floor which gave a grand view of the Bay, but it had fallen into disuse and disrepair. There were protests at the demolition, and both those for an against the destruction used the same argument – that it was one of the last remaining relics of one specific age in Samoa's history. The difficulty was that the age in question was the colonial age, not a period Samoa is especially pleased to recall.

The levelling of that building brings the dilemmas of demolition into sharper focus than does the much publicised pulling down of the statue of Edward Colston in Bristol. Outside the city, few people had ever heard of him, but we have discovered that he was a slave trader, a pitiless man who bought and sold human beings, who was heedless of the suffering he caused to people he no doubt regarded as lesser men and women. His 'business' now arouses revulsion and the fact that he later devoted himself to philanthropy provides no defence of the man or his trade, even among those who view the demonstrators vandals.

Statues and buildings are history in stone, making the problem of destroying symbols of activities now viewed with horror a thorny one. There is agreement that history with all its crimes and sins should not be erased, but its judgments can be revised.

Heroes and victories of the past are continually repainted in different colours, but while it is easy to rewrite a mere book, to revise printed or spoken opinions, to deliver speeches which refute views expressed, perhaps by the same person, in an earlier age, is straightforward enough, but is something deeper lost when a statue is hauled down, a building demolished because of what it represents? Does that mean that we today arrogate to ourselves the right to dismiss our ancestors as scoundrels or fools, and assume that the views we currently hold will be regarded by future generations as beyond challenge?

Buildings can given new uses, as Warsaw did with the monstrous Palace of Culture which Stalin 'donated' to Poland, and which casts a literal and metaphorical shadow over the city. Statues are not so flexible. Their erection and preservation are symbols of respect, so how to behave when that respect is withdrawn?

The toppling of the gigantic statue of Saddam Hussein in Iraq was an iconic moment which gave voice to rage over recent oppression, as was the smashing of statues of Lenin, since those of Stalin had long since been removed following an earlier shift in dominant views, in the countries of the Warsaw Pact as they broke away from Russian domination.

However, in both Budapest and Moscow, the new rulers adopted a more moderate approach. They showed disapproval by removing statues from a central, honoured site to 'sculpture parks' in the suburbs where they could be visited by historians interested in the historical record, but would no longer be an insult to the local population. A huge iron statue of Felix Dzerzhinski, founder of Soviet secret police, used to stand outside the Lubianka prison in central Moscow, and may have been the last sight dissidents saw before being locked inside. It was removed after the dissolution of the USSR and resited in the new park, where it dwarves statues of other figures who once held greater power. A small statue of Stalin is there, available for any gestures of contempt.

Scotland has its own dilemmas, and not only over Henry Dundas in St Andrew's Square in Edinburgh. This statue has caused controversy in recent decades not on account of the alleged financial crime for which he was impeached but because a parliamentary amendment in his name delayed the abolition of slavery. The statue might now be dragged down to the Forth and ditched but the compromise has been proposed of adding an inscription on the plinth setting out his responsibilities.

There is a different dilemma, shared with Canada, over memorials to John A. MacDonald, Scots by birth and first Prime Minister of Canada. Once the high esteem in which he was held was shown by the statuary in cities from Montreal to Ottawa, but he is now abominated for his part in removing the children of native peoples from their parents to have them brought up in British ways. Statues have been smeared in red paint signifying spilt blood.

However, there is a plaque celebrating his achievements in Glasgow on the Ramshorn church where he was christened and a memorial cairn in Rogart, Sutherland, near where he was born. Are they appropriate records to be removed before they are defaced? Or are there other means of noting the changed judgment of history?