> If and how much the colonies made them even richer is debatable, but it was probably a net cost on average. This is one of several insights counter to "common sense" that economists have figured out.
I haven't heard this before, do you have sources where I could learn more?
Acemoglu (last year's prize) has some.
Circumstancial evidence includes:
1. Having natural resources is often bad for development: https://en.wikipedia.org/wiki/Resource_curse
2. Scotland is in the UK because it tried to do colonialism, bankrupted itself and had to sell itself to England.
2. Ireland and Finland are doing as well as any other European country but never colonized anyone and were themselves colonized.
Colonialism is basically just a distracting game countries played before economic growth was invented.
That the West got wealthy from the Industrial Revolution is a commonly accepted fact AFAIK.
We didn't steal that wealth from Africa, in part because Africa had very little wealth.
I don't have a great link laying out this in more detail, but I know Johan Norberg has written and talked a fair amount about this.