Urmm, no, toughness has nothing to do with becoming an officer.
All you need is 60 credits or more from a college or mail in university to go to OCS, and then BLAMMO - you're an officer.
Out of all the Officers that I came across in my 8 year hitch, there were about two who were truly bad assed Mofo's. The rest of them were just normal soldiers like the rest of us, but more educated, and hence, in charge.
Yeah but you have to admit, Officer school is no walk in the park and it isn't the same as basic training. How many officers did you come across that were pussies?
It is also important to note in 1876 ANY soldier was probably much tougher than today's. Life sucked back then.