History of the United States, Vol. I-Charles Austin Beard, Mary Ritter Beard

Many soldiers enlisted from bustling urban environments have spent their lives under the glow of street lamps, making the darkness of the battlefield daunting. Initially, these men may feel disoriented, startled by shadows and clumsy on even ground, overwhelmed by nerves. However, with careful, personalized training, they can learn to move confidently together in complete darkness. Once they build this confidence, further instruction becomes a much simpler task.