Quote from Pa(b)st Prime:
Pretty close in population. 26mil in Iraq, a bit over 30mil blacks in the U.S.
Around 25-30k Iraqis will die in violence this year compared to 10,000 American Blacks. But Compton is in peacetime!!
So I'd say blacks are intrinsically more violent than war torn Iraqis.
http://www.vdare.com/Sailer/050213_mapping.htm
http://www.ojp.usdoj.gov/bjs/homicide/race.htm
The only way you can prove any group is "intrinsically" violent due to one factor is to have a controlled experiment where all other factors are made equal.
Obviously in this case that's impossible. You have too many variables such as ease of firearms purchase in the US, generally much higher murder rate in the US compared to the rest of the civilised world, poverty levels, drug use, organised crime influence, racism etc. However, we can do a 2nd best comparison by looking at other societies and seeing what the murder rates are there, this will at least give us some ideas as to what the most likely causes are. If race is the prime factor, we ought to see very high murder rates amongst blacks in all countries, relative to the murder rates amongst other ethnic groups.
For example, if race were the main factor, then black citizens in Switzerland, Ireland or New Zealand would have a similar murder rate to black citizens in the USA. Whereas in fact US blacks as a group have a massively higher murder rate. This suggests that the main cause of the high murder rate are factors specific to the USA, rather than factors specific to race.
Also if you look at countries like Columbia (mainly Hispanic) and Russia (mainly white/slavic), the very high murder rates there suggest that it's societal and cultural factors, rather than racial factors that determine high murder rates. Spain (hispanic) and Czech Republic (white/slavic) have far lower murder rates despite similar ethnic composition. Same with South Africa versus Lesotho or Namibia, for example.
So, the conclusion best supported by the evidence is that features intrinsic to the structure of a society that are the main cause of high murder rates, rather than pure racial origin. This seems true not only for the US but also for other societies with unusually high violence compared to their economic/social peers.
There's then the question of why do blacks in the US have a higher murder rate than other ethnic groups in the US. The way to answer this would be to look at factors which influence violent crime e.g. poverty, drug use, immigration, policing attitudes, cultural attitudes etc. For example, blacks have a much higher murder rate than asians. Given that both groups were primarily immigrants, you'd look at the background differences between the two to try to reach a conclusion. First, you have the obvious issue of slavery and institutionalised (i.e. legal, versus just societal) racism for much of US history. There were more legal barriers for blacks to advance out of poverty than asians or latinos, up until about 30-40 years ago, and cultural attitudes still persisted for a long time after that (and are still around to some extent). Second, you have the differences in culture between the various ethnic groups. In the US, cultural attitudes amongst some blacks are less in favour of education and hard work than values predominant amongst asians, and there is a much stronger minority subculture of violence & crime. This is in distinct contrast to for example blacks in places like the Bahamas, Barbados etc, where values are much more dominated by traditional conservative attitudes to crime, family & work. This is probably down to the legacy of slavery and then segregation/Jim Crow - cutting off legitimate avenues of enrichment and self-advancement will leave crime as one of the few options for getting rich or getting ahead. You see a similar problem in South Africa which had even more extreme segregation and institutionalised racism - the result was similarly high crime levels amongst the black population. Contrast to for example most of the former British or French Caribbean where violent crime is at much lower levels than the USA.
So IMO the main cause of high violence amongst US blacks is poverty, the legacy of slavery/segregation, pro-crime/violence cultural attitudes amongst a fair minority of black males, drug use & dealing, ease of access to firearms, and the US tendency towards higher murder rates in general. If skin colour were a major contributor, then college educated married blacks in foreign 1st world countries with incomes of >$100,000 per year would also have much higher murder rates than their non-black US counterparts. Whereas US violent crime rates are in fact higher. Educated, well-off US non-blacks commit more murders per capita than educated, well-off non-US blacks. And of course, non-black uneducated Americans in the ghetto are much more likely to commit murder than black university professors in London.
So I can't say I buy the argument that race is the main cause, or that blacks are "intrinsically" really violent. The real cause seems to be that US blacks happened - mostly due to the actions of white mainstream US society over 200+ years - to have been placed in a position where they were most heavily exposed to environmental factors that correlate strongly with high crime rates and violence. US blacks today probably commit so much crime because of their special harsh treatment for the majority of American history, rather than because of any intrinsic racial or genetic factors. If you enslave an entire race and turn a blind eye to lynchings, sexual slavery, unequal treatment in the legal system, then allow effective apartheid in half the country for another 120 years, this is obviously going to have a huge and long-lasting impact on the behaviour, circumstances, and cultural attitudes of those people. It should be no surprise that anti-social tendencies start to surface amongst a significant minority of that population when they are effectively oppressed and excluded from mainsteam society. It takes more than a couple of decades of (relative) progress to erase the damage done.
For mainstream America, this is of course a rather uncomfortable conclusion, which is probably why it is not very popular, and why other specious theories are advanced despite a distinct lack of supporting evidence.