The evil people are not only from those countries.
Those are the biggest mining companies: http://www.mining-technology.com/features/featuremining-gian...
Just an extract:
"Anglo American's wholly owned Minas-Rio iron ore project in Brazil and Sishen mine, part of its Kumba iron ore operations in South Africa are among the world's 11 biggest iron ore mines."
Tell that to the ivory poachers. All a ban accomplishes is turning an industry that has demand underground, meaning they can now operate off the books, illegally, not pay proper wages, operate completely without regulation and if they run into competition, instead of working side one another they often kill each other.
Prohibition has literally never worked for literally anything.
But, sanctions have.
However the bigger issue I think are the few evil people in those countries who look at its natural resources and see dollars instead. They just want to log, mine as much as they can, export it all out and basically make free money. Their business strategy is simple: buy off government personals, acquire natural resources that was supposed to belong to people and sell it off to other countries in the world. You are not going to be able to prevent this either.
One effective way to discourage this is put a worldwide ban of exported wood from Amazon. If major countries can come together on this then this could actually work.