So...a guy is in Army Basic Training, likely heading to the infantry...is being taught to be aggresive and to have quick, forceful and often violent reactions/actions...gets surprised and/or attacked...reacts violently...and suddenly it's a major character flaw and the guy's a bad person?
Wow...just wow. Ain't this a great country?
Having quick, forceful and often violent reactions/actions doesn't cancel having a brain. Being aggressive and violent in, say, HtH is not the same as blowing off @ a buddy in the barracks. So, the SMAJ either decided to go by the book or there was some stuff prior to, that OP hadn't told us about.