Has it occured to you that much of the UK's wealth has left? especially after WWll and guess where it came to? ... The Beattles knew where to go.
I believe that the WWI and WWII loans have been repaid. Another remarkable achievement for the UK!
When I was a kid in the early '50's, the UK still had food rationing and we regarded our country as poor compared with the US. It's all very different now. The recession has hit the UK as hard as anywhere else but the vast majority of people have more material comforts than we did as baby boomer kids.