Before I begin, I'd like to repeat that I don't condone the behavior in this video, matter of fact, I've yet to see it and refuse to watch such brutal and unethical behavior. Having said that, people are absolutely correct in saying that Imperialism, Slavery, Colonization, and other forms of exploitment are partly to blame for much of Africa's current situation. To think otherwise is quite honestly wrong.
Imperialism and Colonization, at their core, are much more complex and wicked then their definitions would suggest. Both boil down to one country injecting culture, religion, infrastructure, ideals, etc to another country, typically through force. Obviously, this is a relatively simplified version of the process but it gets the idea down quite well. People seem to have this idea that these two concepts were simply some civilized countries attempting to domesticate or enlighten a group of heathens (I'm exaggerating a bit) but that honestly couldn't be farther from the truth. Before talking about Imperialism and Colonization, one must look back at the reasons for partaking in such time consuming matters, the answer to this question is the reason the very same reason for Africa's current state. I'll give you a hint, it wasn't out of the bottom of their hearts.
We stripped them of riches, turned them against each other, installed a foreign culture, and pulled out before finishing the job and we were expecting them to come out on top? They got the shitty end of the deal and it definitely shows.
The situtation in the continent simply breeds hopelessness, how are we to expect individuals to overcome such a dire situation? It's not the people that are innately savage, it's the situation they're been trusted into. There's a good reason why crime and poverty are interconnected, compare this list of murders by country (
http://www.nationmaster.com/graph/cri_mur_percap-crime-murders-per-capita) to this ranking of countries by GDP (
http://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nominal) ), I'm willing to bet there is a clear cut pattern.