This is the sort of thing that enemies of Thatcher would do well to remember. Not because it will make them fans of her, but as antidote to the great belief, widespread on the Left, that people on the Right are not just wrong or mistaken or misguided, but evil or mad. There's a curious asymmetry here: people on the Right are quite happy to believe that their enemies on the Left are merely mistaken, perhaps weak or sentimental, but their (bleeding) hearts are in the right place. But those on the Left somehow find it hard to accept that, say, Thatcher, George W Bush or Blair were just normal fallible humans, making what they thought were the right choices given what they knew and believed: for some reason, they have to believe that these people deliberately acted out of evil motives. Jonathan Haidt could explain it.
I would put it this way. Of course Thatcher was an enemy of apartheid. Of course she wanted to end apartheid. Who wouldn't? You don't get any moral points for being on the right side of that debate. (I think she gets the moral points for doing more than she needed to do to make things right, but that is another matter and to a certain extent depends on what view you take of Britain's responsibility for the problems in the first place.) Of course - because she was, deep down, quite like you. And that's worth remembering next time you suspect that George Osborne might be deliberately trying to reduce half the population to destitution for the amusement of his Bullingdon Club chums.