chp. 18

So Henry comes upon this wounded soldier named Jimmie Rodgers. He says he needs water but there is no water for Henry to give him. He kinda looks around and sees all the wounded soldiers and continues to hear gunfire. The camandor tells the regiment that the rebels are forming another attack and that they are suppose to go and fight them. He also tells them that he doesn't know if they will all make it back alive. Henry and Wilson look at each other and are pretty confident that they will make it and do there best.
-Why is he so unsure about this battle?