The irony to your question is that people are people. We are very dramatic. We will watch "Blood Diamonds" and be affected so much by it that we vow to never wear diamonds again. In a few months or years, after we have forgotten we will again wear those diamonds. Because in the end we all know deep in our hearts that refusing to buy the diamonds is not going to change anything, because in other countries in Africa, and all over the world, there are those who are enslaved to do more than just find diamonds. For example there are gold mines too.
Its better to go up against the companies that are exploiting countries like Africa, and demand that they change their policies. Because there is not doubt that in a few years those owners of diamonds weren't place it back on their bodies.
So lets stop lying to ourselves to make ourselves believe that we, humans, are this noble civilized race. This is because deep in our hearts we know that we are savages, and the most malevolent creatures on this planet. A race that will never stop exploiting each other.
The sad part is, it took a movie like "Blood Diamonds" to make so many people realize what is at the tip of our noses.
What a sad society we have created.