I have seen others comment that it is possible stuxnet could also infect systems using "quantum entanglement".. This is not too impossible if you understand the concepts behind quantum computing.

Also, *what if* stuxnet somehow got introduced into these systems via a software update provided by Siemens? This is not entirely impossible. It is very probable that foreign intelligence agents could have infiltrated Siemens. If true, this would be the largest act of industrial espionage in the history of the world.