Since Antiquity, the ideal of virility has been built on the model of the Greek citizen-soldier, notably in war. The Revolution conferred rights upon the soldier, and exalted his courage and acceptance of the supreme sacrifice. During the nineteenth century, Romantics, partisans of colonization, and nationalists continued to base virility in war, while in civil societies a less bellicose masculinity imposed itself. In the twentieth century, increases in firepower, the transformation of combat, and recognition of the fear and psychiatric disorders of combatants, weakened the military-virile model. All the same, the values preached in war and espoused by the army remain first and foremost masculine ones.
Source : War and Virility