Henry wants glory, fame, and honor, which he thinks he can easily get by being a soldier without having to work for it. He thinks that is how he can become a man. He learns that his foolishness and immaturity are standing in his way. Once he makes mistakes, he admits that they were essential for him to grow and see clearly.
|Calico Ghost Town, CA - 2013 Civil War Re-Enactment|
"It had been necessary for him to swallow swords that he might have a better throat for grapes. Fate had in truth been kind to him; she had stabbed him with benign purpose and diligently cudgeled him for his own sake."
I do not believe that he devised a plan to reach his goal; I think it came upon him in an unsuspecting way altogether. He wanted to reach manhood, but his way was foolish. He only realized his manhood after he made numerous mistakes on the battlefield and admitted to himself the truth about his actions. He seems to be contented and self-assured, even if his experience is not the glorious ideal he had created.