Sorry to hear about your brother.
I was there in 1969-70. When my Amvets post got together and we'd "make cow widows" about the time we were there we found that depending on when,where and what service you were in we all fought a different war.
I never saw a jungle, only rubber plantations.
Viet Nam was so new when I went over, I did not have any preconcieved ideas, I can only imagine what it was like for those that came later, after having seen the war through the filter of the bias reporting.
You are right, the war was a different experience depending on when you were there.