Dazbo: "Strange isn't it: All the bad things in the British Empire were done by the English - nary a Scot, Welsh or Irish did anything that we would consider wrong today."

I think the explanation is that on this side of the big water, we tend to refer to the British Isles as 'England' in the same way that Europeans - and Brits - call us 'Yanks'. Or anyone not of obvious other-extraction is assumed 'white'. Blanket designations are not accurate, only convenient.