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Steven Pinker, in his book "The Blank Slate" offers an interesting comparison of savagery over time.  His contention, indeed that of Prof Lawrence Keeley, is that despite all the wars of the 20th century, the per capita rate of violence is lower than all preceding generations.  That is to say, your likelihood of falling victim to violence was far greater in antiquity than it is today.  This speaks to the axiom that democracies are by and large peaceful.

http://www.marginalrevolution.com/marginalrevolution/2004/01/the_savage_sava.html