Good grief,
You hit the guy below the belt without moving an arm. The mark of a true idiot is one that loves the glamour and drama of mud-slinging words, (don't matter if they are right or wrong).
By your silent actions, You effectively denied him the right to continue being unreasonable.
You may never change someone like this, but you can ensure that you will handle any situation correctly the 1st time, (translates to not having to go back & apologize for something said/done while dealing with someone of this caliper).