Britain was a sham anyway. They are a good example of what
happens when you leave your borders open to primitive
cultures. The worst thing they did was virtually leaving
their surfs, subjects, proletariat, etc. unarmed and by law
not allowed to personally defend themselves.
"Primitive cultures" represent perhaps 10% of the British population. Excluding mixed race individuals (who may or may not identify as white), Britain's population is 87% white, compared to the US population, which is only 72% white.
Britain ought to have a lower GDP per capita compared to the US simply because we have vastly greater amounts of natural resources per capita than the British Isles. Apart from Luxembourg, which is a tax haven with no industry to speak of, Norway is the EU's highest GDP per capita nation because it has significant amounts of oil and a small population.
What impresses about Britain is that despite the vast resource gap, the difference between American and British output per capita isn't all that large. For an example of the kind of gap that can exist between two countries with vastly different natural resource endowments, look at Saudi Arabia ($24K) and Yemen $1.4K) - one has abundant oil whereas the other has very little, and neither has significant modern non-oil related industries.
Note also that the US white number (72%) includes Hispanics, many of whom are pure-blooded Aztecs, Mayans and so on from Central and South America.
Britain was and is a great country that built the modern world.
And how many times do we British freepers have to tell you that its perfectly legal for Brits to defend themselves?. The last eight words of your post are utter nonsense.