Joe Anoatubby raises a number of good points, with many of which I find myself in complete agreement. However, one thing I cannot emphasize too much is that generic violence is not a good conceptual category. We need to look at different sides of it separately, for reasons that actually have a lot to do with the main topic of this forum, social evolution.
My article in the Journal of Peace Research very carefully defines what I mean by political instability and what I gathered data on. It is collective violence within states. Thus, I distinguish it from individual crime, such as homicides, on one hand, and from interstate warfare, on the other.
This focus is conditioned by the theory, which attempts to explain instability waves (prolonged periods of political violence) that, if they are strong enough, often result in state breakdown and onset of full-blown civil war. But there are two additional, and equally important reasons to distinguish ‘internal war’ from ‘external war.’
The first reason is related to one of the main topics of the Social Evolution Forum, the evolution of cooperation at the level of whole societies. Internal warfare clearly represents a failure of cooperation within a society. On the other hand, external warfare can only be possible on the basis of strong ability to cooperate. So from the social evolutionary point of view these two types of conflicts are logical opposites of each other and should not be mixed in. To add to this, if warfare is the chief selection force for the evolution of cooperation in large-scale societies, as I and others believe, then by ‘warfare’ we most emphatically mean ‘external warfare.’
The second reason is actually related to the first. In historical record internal and external wars tend to be negatively correlated. If a society is torn apart by an internal war, it is hardly in position to prosecute a successful external war. This is why there is an empirical pattern that most territorial expansion due to conquest is usually accomplished by societies who are in their integrative secular phases, and they often tend to lose territory while in disintegrative phase. See, for example, my book Historical Dynamics (the sections on France and Russia at the end). Furthermore, being attacked by an external enemy usually makes a society more cohesive – different political factions forget about their petty quarrels and unite to repel the common foe.
But the relationship between internal and external warfare is more complicated than a simple negative correlation. First, many a ruler, facing growing discontent by the populace and the elites, has tried to solve his problems by a ‘little victorious war,’ only to find things going disastrously wrong, losing legitimacy, and triggering the very revolution that he tried to avoid. Second, when a country decends into revolution and civil war, the neighbors are tempted to intervene, as happened in the wake of the French Revolution, which helped to trigger the French Revolutionary Wars.
So both social evolutionary logic and my experience in analyzing historical dynamics suggest that it is best to keep internal and external warfare as separate conceptual categories, and then analyze the complex interactions between these two variables, rather than lump them together.
Let’s apply these general insights to the American history. First, note that the two periods of internal peace in the U.S. coincided with a very vigorous pursuit of external wars. In fact, these were the periods when the U.S. was really threatened by outside players, rather than getting involved in ‘wars of choice.’
The first such period was the first half of the nineteenth century as Joe points out. This was when Americans were attacked on their own soil (the White House burned and New Orleans attacked by the British during the War of 1812). This is not to say that the Americans were the victims, far from it…
But much more important were the recurrent conflicts between European Americans and American Indians, which was pretty much nonstop from the Revolutionary War to the Removal Era Wars (so, from 1775 to 1842). In my book War and Peace and War I discuss how these wars, and American Indian wars in general, played the decisive role in the social evolution of the U.S. In general, these were very bitter wars, characterized by atrocities on both sides, and eventually by successful genocide on the part of European Americans.
The second such period was the World War II, when Americans again were attacked on their own soil (although a fairly remote part, the Hawaii). Again it was a period of national consolidation which contributed to the decrease of internal instability.
Note that these two periods were also when the United States dramatically expanded its geopolitcal reach. It became the continental power between 1776 and 1848 (the only other major addition was Alaska), and it became a world hegemonic power in the post-1945 period.
Returning to Joe’s points, I believe that we should treat American-Indian wars as external wars and distinct from internal instability (and in fact, negatively correlated with it). This is the approach that I adopted in the JPR article, where I treat Indian-American conflicts as instability only after the ‘official’ closing of the frontier in 1890 (and there were few such events, anyway). During the Antebellum period the U.S. may have regarded the Indian territories as their own, and suppression of Indians as an internal matter, but this was certainly not the Indian point of view, most of whom considered themselves as separate nations.
Finally, a useful concept here is ‘parochial altruism,’ which is the tendency to cooperate with members of in-group to better compete against the members of out-groups.
I think the above offers a very useful conceptual framework to view the empirical facts so well summarized in Joe’s post.