From Army NCO History (Part 2): War of 1812...:
"In February 1812, Congress ordered the creation of a 50,000-man volunteer army. When war was declared on Great Britain in June 1812, there were roughly 7,000 men in the regular service; many were under the command of senior officers who lacked experience in combat or leading troops."
"It fell on the NCO corps, specifically corporals, who were the primary trainers at the time, to prepare the Soldiers for combat against the British."
It has to be remembered that there was a distrust among the populace of a standing army; militias.... .