When reading Afghan Hearts & Minds, I found instances that indicated that Afghan men and American men have similar repressed emotions when associated with crying. Both of the societies promote the idea that a man who cries is weak. This could be caused by constant war, or the concept of obtaining a sense of ruggedness.
Either way, this repressed emotion can explain much of the violence that is widespread in both countries. When men hold back these emotions, it can result in violence in compensation.
The key to remove the violence in both of these countries may to be to allow men to express their emotions more acutely and openly.
Here is article that goes in detail in about men's crying as compared to women's crying: