, it led to the belief, president assad's belief, that there is no communication in syria-- you name it, s.m.s, telex, g.s.m., e-mail, regular phone, cellular phone-- that is not bugged by israel signal intelligence unit. every time mustafa called muhammad, moshe was listening. >> warner: now, he says, that surveillance effort has intensified further still, as israel works to head off any transfer. what do israeli's fear the most about chemical weapons? >> if israel is convinced that syria is supplying hezbollah with chemical weaponry of any sort, it would be deemed as crossing a red line, and israel would conduct a preemptive strike. period. >> warner: do you think the u.s. and israel are on the same page with how to deal with syria? chemical weapons threat or anything else? >> yes. yeah, i think that on this it's a unique topic where president obama and prime minister netanyahu do not differ. >> warner: yet despite the potential threats of the unknown that lie ahead in syria, bergman believes the collapse of the assad regime would be good for israel's security. >> they always say that israel