With all due respect, (and I am speaking only for myself and I am not a veteran), it isn't an issue of stiffling free speech.
I find it very innapropriate to be arguing the Viet Nam War on this thread. Most have come to pay respects.
Zarf can start another thread, he's free to do so and no one would challenge his right to speak on that thread. (Although it would be a fiery debate, I am sure).
IMHO, starting the debate about the merits of this Viet Nam War on this particular thread is the same as going to the funeral home arguing this issue in front of the casket.
But, that is just my opinion.