While Henry displays the most self-doubt among the three, the loud soldier and the tall soldier already have decided how they will fair in their first taste of combat. Jim Conklin (the tall soldier) is realistic in his assessment of his expectations. He admits that he may run if the rest of the company runs, and that
"... if I once started to run, I'd run like the devil, and no mistake. But if everybody was a-standing and a-fighting, why, I'd stand and fight. Be jiminey, I would. I'll bet on it."
But Wilson (the loud soldier) claims to have no question about his abilities. He laughs at the proposition that he might run if the action gets too hot. His bluster will later prove to be gross overconfidence. Behind this act is an uncertainty no different than Henry's own self-doubt. But Wilson prefers to loudly proclaim his manhood, and how he will "try like thunder."
He evidently complimented himself upon the modesty of this statement.
“Run?” said the loud one; “run? of course not!” He laughed... I'm not going to skedaddle. The man that bets on my running will lose his money, that's all.”