REASONABLE DOUBTS
Critics of the democratic-peace hypothesis make two main counterargument. Their first line of attack holds that the apparent pacifism between democracies may be a statistical artifact: because democracy have been relatively rare throughout history, the absence of wars between them may be due largely to chance. Evidence for a democratic peace also depends on the time periods one examines and on how one interprets borderline cases like the War of 1812 or the American Civil War. Critics also note that strong statistical support for the proposition is limited to the period after World War II, when both the U.S.-led alliance system and the Soviet threat to Western Europe's democracies discouraged conflict between republics.
A second challenge focuses on the causal logic of the theory itself.Democratic-peace proponents often attribute the absence of war between republics to a sense of tolerance and shared values that makes using force against fellow republics illegitimate. (As noted above, Weart's version of this argument emphasizes the tendency for republics to see similar states as part of their own "in-group.") If this theory is true, however, there should be concrete historical evidence showing that democratic leaders eschewed violence against each other primarily for this reason. But critics like Christopher Layne have shown that when democratic states have come close to war, they have held back for reasons that had more to do with strategic interests than shared political culture. These cases suggest that even if democracies have tended not to fight each other in the past, it is not because they were democracies.
Instead of meeting these challenges head-on, Weart assembles his own body of supporting evidence and devises his own explanation for the apparent lack of war between republics. Although his arguments should not be dismissed lightly, Never at War illustrates many of the limitations that have marred this debate since its inception.
To begin with, Weart's treatment of historical materials is hardly even handed. He is quick to embrace evidence that supports his argument and even quicker to reject evidence that challenges it. Thus, he dismisses in a single footnote the claim that the democratic peace maybe a statistical artifact and treats the work of other skeptics with equal disdain. He also excludes the various wars between the Roman republic and its neighbors, including the brutal Punic Wars with Carthage, on the grounds that "no primary sources nor reliable secondary sources survive." Yet he does not hesitate to use otherancient sources that buttress his claim, such as Thucydides and Xenophon, even though they are by no means perfectly reliable. Modern classicists generally agree that both Carthage and Rome were oligarchic republics, which suggests that excluding them was a largely arbitrary judgment that just happened to leave Weart's central claim intact.