What percentage of London is white?
No idea. A large part of London arn't even citizens, they just work there (at least 200,000 French people work there for example, 123,000 Polish people, about 200,000 Germans, plus traders in the City from all corners of teh world, plus Irish commuting in from Dublin, and so on).
Who cares as long as they pay their taxes?
Other examples of what foreign countries could class as "mixed" but what we just think of as "Brits" - the Earl of Liverpool, who was Prime Minister from 1815 to 1827 (he had a Gujurati grandmother), Seb Coe (Olympic athlete who organised the 2012 Olympic games - he has a Hindu grandfather), Ian Duncan Smith (cabinet minister - Japanese grandmother), Jessica Ennis (Olympic athlete - Jamaican father) and so on.
Nobody looks at these people and thinks "ethnic minority". They've been absorbed and the dominant language and dominant culture remains exactly the same over time.
In Britain, it's
class not race that divides people. If you are the right class, doors open for you regardless of your ethnicity and if you are the wrong class, doors shut regardless of ethnicity. Sooner of later people figure this out and "marry into" a level up. The Middletons are a classic case in point. On her mothers side, Kate Middleton has a bit of mining background, plus a bit of Jewish background. So if we still have a monarchy in a 100 years time, the king will be a descendant of a miner and a descendant of Jewish immigrants, as well as descendants of the other kings from his father.
Can't see that happening elsewhere. Look at the fuss people made about Obama for goodness sakes. I guess the Earl of Liverpool would really have shocked Americans back in the early 19thC if they'd known his roots!
