The first one was a family member (although not my grandmother(, in response to the television news, which was on Israel.
Exact words burned on my mind: "I think Hitler had a point". I fully expect that other MNers may consider this a light-hearted comment. I don't.
I did as I always do, except that was early on in my career of not nodding-and-smiling, and so there was more stammer and my absolute astonishment overlaid a great deal more fear. I explained what I thought she'd said and what that meant, and did she really mean that (answer boiled down to "yes" and "it's what everyone thinks"), and what that meant in human terms, and then pointed out that modern Israel would most likely not even exist, never mind in its present form, if it wasn't for Hitler's actions. I think I remember going into great detail about international politics circa 1947-'49. Fortunately for me, the formation of Israel had been something I'd been reading about. I wouldn't do so well now in a similar argument on facts.
Conclusion: she thinks I'm very PC, but she doesn't say that around me any more to avoid an argument.
Second one, also family member (also not my grandmother- this may actually be why people don't cross the road from me, they have low standards due to the opinions of my relatives, and I seem really pleasant in comparison
). This one was less justifying genocide, and more belittling it, to be fair.
"I'm fed up of the Jews complaining about the Holocaust. The street my mother was born in was destroyed, but no-one talks about that". I can't remember my exact response but I think I pointed out that massive scale of human life lost and the deliberate circumstances were a bit worse than one street being destroyed. (He didn't even complain about the loss of British lives. Just that street!)
Then he said, "Hmmm. But those Israelis look pretty shifty on the TV". I think I said that all the ones I'd seen on the TV had been politicians, and that in my opinion, all politicians look pretty shifty on the TV including British ones, and that even if Israel had the only shifty politicians in the world, their citizens would still be entitled to demand that Europe remembers the holocaust.
Possibly a bit offensive to politicians, admittedly, but again, I was still throwing off the shackles of "you should laugh offensive things off".
I don't generally see him very much, and he wonders why, because I was a bit too polite at the time about it.