Civil conflict over the second half of the 20th century have become increasingly dominant.

Over the second half of the 20th century, conflicts within national boundaries became increasingly dominant. One-third of all countries experienced civil conflict. There are two remarkable facts about social conflict that deserve notice: first, within-country conflicts account for an enormous share of deaths and hardship in the world today, and second, internal conflicts often appear to be ethnic in nature. Which factors influence social conflict? Do ethnic divisions predict conflict within countries? How do we conceptualize those divisions? If it is indeed true that ethnic cleavages and conflicts are related, how do we interpret such a result? Is ethnicity instrumental to achieve political power or economic gain?

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