"Saddam only allowed hard wire which is easiest to bug..."
Sounds more like SADDAM was the 'bugger' in this case. I know what you are thinking, when I first read it, so did I!
We don't know how old those towers are. They may have existed since before Saddam came into power. I think the inference is that under Saddam no repairs were made. (counter-productive.) The shia majority were his victims, therefor he would hardly repair a system that allowed them to communicate, (I think.)
Maybe both saddam AND Berg "bugged". 'm still thinking that Nick Berg was not the person that he has been reported to be.