Moustaches will never take again in Ireland for a number of reasons - one of which is the fact that everyone's Da in the '80s had one and we associate them with that.
More to the point, some of our most noteworthy politicians had them in the '80s and some continue to do this. Willie O'Dea, John Halligan, Liam Cosgrave, Sean Haughey, and of course, Dick Spring - they all had moustaches and they're all ingrained into the public consciousness of Ireland.
Therefore, when you see someone with a moustache nowadays and you're Irish, your mind calls back Dick Spring et al - and that's what happened to Ruth Negga when she sat down with Jimmy Fallon last night.
Fallon, who's taking part in some sort of stunt called Summer of 'Stache, felt like it was a compliment. Jimmy - or Jimmy's people - it's not a compliment. At all.
This is Dick Spring, the politician Ruth Negga was most likely thinking about.