Earlier quoted context omitted.
At this point, I'd say terms rather than generations. I mean, I'm old enough to remember people saying "Never Forget" about 9/11, but it's barely in any discourse at this point, and that was a single generation ago and had two major wars a bunch of PoW scandals, war crime scandals that led to Manning, and domestic surveillance that led to Snowden. And yet, despite all that, I've only heard 9/11 mentioned exactly once…
You are talking about the US, the others do not.
I mean, I live in Germany these days, and this country absolutely got the multi-generational thing, and I'm from the UK whose empire ditto, but… the UK doesn't spend much time thinking about the Falklands War and even less about the Cod Wars.