This week I've been reading Nancy Sherman's book Stoic Warriors: The Ancient Philosophy behind the Military Mind, which not only looks at how Stoicism can apply to the modern military (and how much military codes and standards dervie from Stoic thought), but also provides a nice introduction to Stoicism itself, combatting common (and often) mistaken ideas of it as denying emotion altogether, rather than recommending self-regulation of emotion, allowing it when appropriate and suppressing it when not.
Chapter 3, "Manners and Morals," contains a defense of military decorum, encompassing all the many elements of it, including dress, movement, and speech. In the following passage, she discusses the importance of the voice:
...how officers address their troops can be an index of character and excellence. A tone of voice that is stern but not abusive, objective and authoritative yet still compassionate, is a way of commanding (deferential) respect and showing (dignitary) respect. It is a sign that can reveal a leader's good character and sensibilities. (p. 57)
She then goes to cite from Cicero's classic guidebook On Duties, particular Book I: 133-137 on public speaking--such as "One ought for the most part only to resort to mild criticism, though combined with a certain seriousness so as to show severity while avoiding abusiveness" (137)--and applies it to military command:
The character and tone of one's voice are part of the example one sets. True, not all are gifted orators like Pericles, who gave a funeral oration for Athenian troops that came to define the species for all of history. But all have an obligation to find ways of commanding with seriousness and resolve, and with a respectfulness that still lets subordinates know who is in authority. (p. 57)
When I read this chapter in Sherman's book, I thought of how Captain America has been portrayed in comics over the years, especially as regards his voice and the influence and authority it commands. My favorite example of this comes from Daredevil #233 (August 1986), the final issue of Frank Miller and David Mazzucchelli's classic Born Again storyline, in which Ben Urich sees Cap giving orders to Thor, and thinks, "A soldier with a voice that could command a god--and does." The Thunder God's respect for Steve Rogers can been made evident ever since the Avengers thawed him out decades ago, and his demeanor in commanding his "troops" is certainly one factor behind that respect that a god gives a man in this case.
Another fantastic example of Cap's authority comes from Avengers #63 (March 2003), final chapter of the Standoff storyline that crossed over with Iron Man and Thor. Here we see Cap trying to keep the American military from escalating a tense situation with the Russians (instigated by Doctor Doom):
(Scans courtesy of Scans-Daily's post on this issue, which makes a similar point about Cap's authority.)
Here we see Cap command the U.S. soldiers, his voice stern and firm yet respectful--and also showing respect for the commanding officer at the same time disagreeing with him. But when he gives the order to "stand your ground," we "hear" the voice that commands men and gods alike--and a voice that Cicero and his fellow Stoics would have admired as well.