Republicanism in the United States
However, at this time, the word "army" meant "foreign mercenaries."  After the Revolutionary War, Americans did not trust mercenaries.  Instead, they came up with the idea of a national army, made of citizens.  They changed their definition of military service from a choice of careers to a civic duty  something every good republican should do.  Before the Civil War, people saw military service as an important show of patriotism, and a necessary part of citizenship.  To soldiers, military service was something they chose to do, something they had a say in, and it showed that they were good citizens.