Less than a decade ago, only the most imaginative of minds could have foreseen that the haunting strains of "Nkosi Sikelel I Afrika" would echo from the ancient timbered ceiling of Westminster Hall as members of parliament and of the House of Lords, stood solemnly to attention.
Mrs Thatcher, when Prime Minister, had described Nelson Mandela, a prisoner on Robben Island, as the leader of a "terrorist organisation" and refused, with characteristic stubbornness, to join the rest of the world in imposing sanctions on a regime which had withheld all legitimate means of political expression from the vast majority of its people.
Yesterday she also stood for the anthem which calls for God's blessing on Africa and sat silently to listen to the balanced words of President Mandela, the first democratically elected South African leader. In Mr Mandela's own words, a two hundred year old circle which began with British colonisation of southern Africa had finally been completed. His own inherent probity and dignity prevented him from adding that no one played a greater part in closing that circle than he did himself.
Perhaps the greatest attributes he has brought to bear on the post apartheid situation in his own country has been a total lack of bitterness and a complete denial of revenge as a political motive. This was evident again in the historic confines of Westminster Hall. He was frank about Britain's colonial legacy and its contribution to white supremacy in South Africa.
It was a simple statement of historical fact engendered not by bitterness but by an accurate interpretation of history and it was followed by praise for British politicians and churchmen who did more than most to rectify the situation which their country had helped create. He had come, he pointed out, not only to the land which had laid the original basis for the apartheid system, but to the land of William Wilberforce who had dared to stand up to demand that the slaves be freed and to the land of Fenner Brockway who had worked for colonial freedom.
Mr Mandela has suffered far greater privations than many who consider themselves oppressed, yet he has spoken calmly. He has spoken in Afrikaans, which he once knew as "the language of the oppressor," to the men who had finally come to the realisation that their "great dream" of a state based on intolerable racism had come to an end. He has, without exception, spoken in the mild tones of the statesman rather than the strident pitch of the demagogue.
This even handedness, this stressing of the positive over the negative, is something that less eminent politicians nearer to home might strive to copy even if their qualities may never match up to those of the world's greatest and most admired living politician. South Africa has been fortunate to have had a man of his calibre arrive on the political scene at such a crucial time in its history. The invitation to address the joint houses of parliament has been described as a rare honour. The honour bestowed on the joint houses has been no less rare.