People who choose to serve in the military are different from those who don't. The experience of military service then exaggerates the personality differences in small but significant ways, which remain that way when soldiers return to civilian life. These personality differences may play a role in the veterans' high divorce rate, and their other social and occupational problems.
These are the conclusions of a 6-year study, conducted by Joshua J. Jackson and teams of researchers from Washington University in St. Louis and the University of Tubingen in Germany, published in Psychological Science.
In one of the first empirical, prospective longitudinal studies of personality change in adults, the researchers followed German male high school graduates who chose to fulfill their public service obligations in either civilian or military settings. Those who chose military service were generally less neurotic, less likely to worry, and less interested in seeking novel experiences. It is no surprise that they were also less agreeable, i.e., more aggressive, more interested in competition than cooperation and less concerned about the feelings of others than their civilian counterparts.
Being lower on Agreeableness, the personality factor (in the Five Factor Personality Inventory) that also includes warmth, friendliness, and kindness, may not be a bad thing for a soldier. Low Agreeableness may work for certain other situations, as well. But a less agreeable personality is an obstacle to forming and maintaining romantic, family and friend relationships. It can be a problem in the workplace, too.
So it is enlightening, but also a cause of concern, that the study found even greater differences in Agreeableness between the soldier and civilian subjects years after military service, when they had returned to work or school. A disagreeable personality is a social handicap.
The knowledge that military service makes soldiers' personalities less agreeable is important information. It sheds light on the struggle many veterans face in family, social and occupational life. It is an insight that needs to be understood and incorporated into programs that aim to help them adapt and find satisfaction in civilian life.