For example, the two most dangerous regions are Latin America and sub-Saharan Africa. Both have murder rates of about 20 per year per 100,000 population. North Africa is 5.9 and North America is 3.9. Europe is 3.5 and Asia is 3.1. Some of the differences can be attributed to the easier availability of firearms (Cold War surplus AK-47s and other infantry weapons), especially in Africa, in the 1990s (after the Soviet Union and several other communist dictatorships fell and their vast weapons holdings hit the arms market), making the frequent tribal conflicts much deadlier. Before the cheap AK-47s hit Africa, Latin America had long been the most violent place on the planet.
This dire situation has long been recognized in South America. Five years ago the Organization of American States (OAS) issued a study reporting that there are 80 million privately owned firearms in Latin America. For a region with 550 million people, that's a lot of firepower. There were 90,000 attacks using firearms in 2007, which is about 16 per 100,000 population. Add other deaths from knives, machetes, blunt instruments, and so on and the rate goes to over 20.
At that time the murder rate in the Western hemisphere (about 8 per 100,000 people a year) was much higher than in Europe, where it has long been between 3 and 4. Middle Eastern nations have likewise varied between 5 and 10. The United States is often regarded, at least by Europeans, as a wild, gun happy place. But the national murder rate has been declining for two decades and is currently about 4.8 per 100,000. There are other parts of the world that are more violent. Iraq had a murder rate of 26 at the height of the Sunni terrorist campaign in 2008, now it’s less than a tenth of that. Under Saddam the murder rate was 10-20 a year. In Africa, especially Congo, Sudan, and South Africa, you find rates as high as 30 or more.
While firearms make it easier to kill, they are not necessary for a high murder rate. Parts of Asia, Latin America, and Africa have murder rates of over ten (or much more) per 100,000, without the presence of many firearms. To lower the murder rate something has to be done about anger management, more so than weapons control. Criminals can always get banned weapons, and in some parts of the world the anger issues are much worse than in others. Corrupt and ineffective government is the most common cause of anger, and this has been a problem that is difficult to deal with.
Frontier areas have long been noted for less law and more violence. The Western Hemisphere has retained many traits of a frontier culture. Tribal societies are more violent than those using more advanced forms of government (monarchy, democracy), a fact which is often ignored. But anthropologists, archaeologists, and historians continue to uncover more evidence that tribal systems are very violent and have always been so. Add more effective weapons to this and you get massive deaths. One reason for the enormous population growth in Africa after the 19th century was the European colonial rule stopped the incessant, and debilitating, tribal warfare. While the colonial administrations were none too gentle, tribal wars often ended up in the extermination of the losing tribe. Over the last half century, the new governments in Africa have continued to police the many tribal conflicts but the introduction of cheap AK-47s make this much more dangerous for the security forces.
In Latin America (Colombia) and Asia (Afghanistan and Burma) the production of heroin (and other opiates) by criminal gangs provided so much money that these gangs (often joined by rebel groups) were able to arm themselves so well that the local security forces were put on the defensive. Taking down these drug gangs cost a lot of lives, especially when they were aided by existing rebels (the Taliban in Afghanistan and leftist groups in Colombia). These drug gangs rose to prominence starting in the 1960s (Burma and the “Golden Triangle”). The heroin trade was eventually driven out of Burma and ended up in Pakistan’s tribal territories and was quickly pushed across the border into Afghanistan. The Colombian drug gangs have been driven into neighboring nations over the last decade, lowering Colombia’s murder rate and increasing it next door.