Also Mandela had the eyes of the world on him (and those of plenty of Western leaders who had not so much supported apartheid, but were happy to trade with SA) and knew that if he lost control of the situation that there may have been a genocidal bloodbath on the cards once the tables were turned. That he achieved a relatively peaceful transition of power was probably the best thing he managed.
The situation differed greatly in Northern Ireland, and while there was reluctance on the part of Unionism to hand over control to Nationalists and allow RoI to have a say in cross border matters, the unionist chunk of the population wasn’t fearing a bloodbath.
Powell’s book on the negotiations that led to the GFI is worth a read, particularly for those with more sympathy for Nationalism than Unionism, as it gives a good insight into unionist mindset. I came away from reading it with a bit more sympathy for their position than I had previously. Bear in mind that they brought two sides into a power sharing agreement when previously some of them wouldn’t even sit in the same room as the other “side” to begin with.
McGuinness and Paisley came a long long way together and without their changes and those of Trimble also, we wouldn’t have the relative peace that exists today.
Brexit and the unionist’s mis-management of the renewable energy scandal have both thrown spanners in the works but I have hope that as the reigns of power are passed on to a generation not involved in the troubles, they’ll manage the peace ok.