Distribution of wealth within a specific Country is usually a good reflection of the economic system in place, i.e. capitalism, market economy, etc. (see U.N.).
For example, in the United States at the end of 2001, 10% of the population owned 71% of the wealth, and the top 1% controlled 38%. On the other hand, the bottom 40% owned less than 1% of the nation's wealth.
Distribution of wealth Norway: http://www.ssb.no/norge_en/inntekt_en.pdf
BTW, Norway is a Kingdom, and definitely 'not a socialist Country.'
Mexico is a example of a Country with natural resources, a corrupt political system, and very little 'trickle down' to the general population, resulting in inequitable distribution of wealth.
Without the labor market for illegals in the U.S. acting as pressure valve, Mexico might have seen a Revolution, and change in systems.
While U.S. politicians continue to ignore it, there is a very real threat of a leftist system coming to power south of the US border.