NAFTA's been written about by Carlos Guerra, a San Francisco journalist. In his article, he cites different people saying the distribution of wealth has been mismanaged, and that only corporate rights are being taken into account. In my own analysis of NAFTA's impact, I've found that while GDP has grown, Canadians' average salary has not, which means the growth is going to companies.
While I can't say I've found any causal links to social problems (in the sense of quality of life issues; the environment, life expectancy, literacy...) like Guerra has, his article is well worth reading, not to mention it's concise and to the point.
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