If one walks through the cemetery at West Point Military Academy there are quite a number of graves containing Lts and Captains from the Vietnam War.
Some of them even killed by the enemy.
I graduated from Infantry Officer’s Basic (IOBC) at Ft. Benning in Nov 1967. Training was for newly commissioned 2LT’s or 1LT’s (lawyers) who had never been on active duty. The urgency of the training was emphasized by the instructors who were combat veterans. “Learn this or your dick will fall off, learn this or you’ll die in Vietnam” was the running joke. But not so funny. Many in my class of 270 died in combat in Vietnam, including the one who graduated first in the class, and the one who graduated last in the class.