Maybe coincidence, maybe not. I happened to be crossing the border back into the U.S. from Niagara Falls on Thursday afternoon when the Customs and Border Patrol computers at the entry port started to randomly shut down. It took over two hours of waiting for them to finally call the ATF to run our passports. Lo and behold, the FBI system was their backup! This is the side-effect of inter-agency connectivity: if you CAN successfully launch an attack, you can take down EVERYBODY.

But these examples are hard-wired (or -coded) responses to specific stimuli/criteria. The entire Terminator premise is that the AI is able to extrapolate from specific situations to a general situation (i.e. all humans without a "friend" transponder/RFID/etc. who are behaving in a specific way are a threat, to ALL humans are a threat). I'm not a roboticist, but it seems to me that this leap of "logic" is not at all inevitable.