In the U.S. Army of 2010, the regulations state that mustaches are limited to men, and the length and shape of the mustache itself is severely limited:
“Mustaches are permitted; if worn, males will keep mustaches neatly trimmed, tapered, and tidy. Mustaches will not present a chopped off or bushy appearance, and no portion of the mustache will cover the upper lip line or extend sideways beyond a vertical line drawn upward from the corners of the mouth. Handlebar mustaches, goatees, and beards are not authorized. …they are not authorized to shape the growth into goatees, or ‘Fu Manchu’ or handlebar mustaches.”
Despite their ranks as generals, these two Civil War soldiers would not meet the stringent policies of today’s Army regarding mustaches. General Poe has a goatee; and while it is not a “Fu Manchu,” Blunt appears to be sporting a soul patch.
Only 150 years later, these mustaches are not only unfashionable, but they are even outlawed. What could have caused such a change in military mustache policy?
Gas masks for ground pounders and oxygen masks for aircrew.