I know I am slow, but what reason would "our intelligence" have for not revealing what you suggest was Berg's spying for the terrorists? The only shred you seem tosay is that they warned Berg but then somehow "left him open". That's appears pretty thin.
The is an intelligence war and a political war being waged behind the real war.(Think spy vs spy if you want a more simpler explanation). Berg's father is a well known leftist political operative in the Philly area who is well known for his activist activities.
Nick Berg is all over the place and he also shows up on Michael Moore's radar screen...come on put the pieces together!
The Bergs were up to no good...our intelligence knows they were up to no good...and thus Nick Berg,though given a life line to leave Iraq, was hung by his own rope in-stead. Berg's dad knows and he also knows that we know...but no one is going to really talk about it.
The only real reaction Berg's dad is showing is an unbounded rage at the Bush administration and little grief for his own son.
If such as above were the case, then I hope the dad rots from the inside out!