>could it be, the west needs to suffer economically for developing parts of the world to prosper?
Very, very unlikely. The most relevant example of a modern fall from economic grace is the descent of Argentina, from the seventh-richest country in the world in 1900 to somewhere around 50th today. However, if anything, this had a large negative effect on the economy of South America (which stagnated as Argentina fell), and the modern economic rise of Chile and Brazil seems to be helping the countries surrounding them, or, in essence, prosperity is contagious, rather than conserved.
Very, very unlikely. The most relevant example of a modern fall from economic grace is the descent of Argentina, from the seventh-richest country in the world in 1900 to somewhere around 50th today. However, if anything, this had a large negative effect on the economy of South America (which stagnated as Argentina fell), and the modern economic rise of Chile and Brazil seems to be helping the countries surrounding them, or, in essence, prosperity is contagious, rather than conserved.