Blanche Dubois may have famously depended on the kindness of strangers in the closing scene of Tennessee Williams'A Streetcar Named Desire, but in a world fraught with treachery and deception, most of us prefer to depend instead on the kindness of friends and family to help us through hard times, and reciprocate when called upon to return the favor. But are there limits to what we'll do to sustain the bonds of friendship?
In their new book Heroes and Cowards, economists Dora Costa and Matthew Kahn use the Civil War as their laboratory to study what men will do in the name of friendship. They find that men serving in companies with tight social connections—like shared birthplace and occupation—were more likely to stand and fight than those in less tight-knit companies, where desertion rates were up to four times higher. The bonds of friendship also mattered for Union soldiers who ended up in Confederate POW camps: Soldiers imprisoned with others of similar backgrounds were much more likely to survive to see the war's end.
When economists look at friendship and social networks, what they see is people trading favors—you scratch my back and I'll scratch yours. A friendship's value is determined by the benefits of favors you receive weighed against the cost of the favors you'll need to do in return. A friendship built on cold economic foundations can be sustained only as long as the gains of the long-term trading of favors exceed the benefit of taking one last back scratch before putting an end to the relationship (though news travels fast, so retaliation from others in your social circle may help to keep you from taking advantage of others).
Of course, for all but the most calculating of individuals, there's more than naked expediency to friendship—we help others because we care about their well-being rather than what it gets us in return. At an extreme, this concern for others can lead us to do things like giving up kidneys or falling on hand grenades to save our friends—acts that can't be good for our long-term health. So friendship can help us in our daily lives but can also prove very costly because of the extreme sacrifices that emotional bonds may inspire.
Much of the evidence on the nature of favor-giving among friends examines situations that aren't exactly life-or-death. Costa and Kahn look at the larger stakes decision of whether Union soldiers chose to risk death by remaining to fight or desert and save their own skins. The authors reason that social bonds are stronger among soldiers from similar backgrounds. New England-born soldiers, for example, will feel greater kinship with other New Englanders, the Irish with other Irish, blacksmiths with other blacksmiths. In companies where men had shared backgrounds, fewer soldiers would be expected to abandon their comrades, both because of the greater kinship among men with a sense of social connection and because their shared network would make it easier to punish and censure cheaters back home.
The military service records of every Union soldier—including birthplace, occupation, age; whether he deserted, got captured, won a Medal of Honor—were sent to the National Archives after the war. To test their theory, Costa and Kahn analyzed the records of soldiers in 354 Union companies, a total of 41,000 men. They found that on average, nine out of 100 men deserted. However, in companies populated by a relatively homogeneous group of men—of similar ages, born in the same place, who worked similar jobs before the war—the desertion rate was closer to two in 100. Belief in the cause mattered—enlistees from pro-Lincoln counties were less likely to desert. And the likelihood of catching a bullet by staying and fighting naturally figured into soldiers' decisions to go AWOL as well—desertion rates went down when the war tilted in the Union's favor. But neither belief in the war nor hopes for survival mattered nearly as much as the strength of social bonds in predicting who would stay and fight.
This wasn't because soldiers felt safer surrounded by friends whom they could count on for life-saving favors—a soldier's best chance at survival was to desert, regardless of the strength of his fighting unit. Rather, it was the shame and embarrassment of abandoning one's comrades. A community quickly got word of cowardice as well as heroics through soldiers' letters home, and deserters were nearly 50 percent more likely to pick up and move to a different state after the fighting ended.
If your goal was to survive the war, the bonds of friendship, then, actually worked against your interests—your best shot at staying alive was to run for the hills. But for the unfortunate thousands who were captured, herded onto cattle cars, and shipped to Confederate POW camps, easy escape was no longer an option. Circumstances in many of the camps were more perilous than the war's front lines. More than 40 percent of inmates at the infamous Andersonville Camp in southwest Georgia perished, mostly from scurvy, diarrhea, dysentery, and other diseases of malnutrition and overcrowding. Yet for men who were lucky enough to get captured with a ready-made social network, chances of survival were far greater. An Irishman who was captured with enough other Irish company-mates, for example, had a better than 90 percent chance of making it to the war's end. Why was friendship such a crucial resource in surviving as a prisoner of war? The camps were overcrowded, rations in short supply, sanitary facilities nonexistent. Survival required the care of friends if one fell sick, the sharing of food, shelter, other resources, and protection from looting by other prisoners.
For Civil War soldiers, friendship was thus a double-edged sword—on the front lines, the obligations of friendship cost more than the benefits; in the camps, the situation was reversed. In these difficult economic times, many Americans are finding themselves in need of friends to lean on for financial and emotional support. But friendship is once again proving to have its costs and benefits. Trust among friends is a source of vulnerability well-recognized by hustlers and conmen. It proved to be the undoing of the Jewish and Palm Beach communities that were victimized in the $50 billion pyramid scheme concocted by Bernie Madoff, one of their own. With friends like these, maybe Blanche was onto something after all.