Its a perfectly legit comparison to make between a capital and other cities within the same nation.
You can compare London with a village in the UK or a small town too if you like - point I was making was that you wouldn't really be comparing like with like.
There aren't really other cities within the UK that come close to its size/status.

I honestly believe he's the type to cross the road or walk another way if he sees a group of 'coloured' people together.
).
