Someone never watched the Terminator series.
In all seriousness, if we ever get to the point where an AI needs to be shut down to avoid catastrophe, there's probably no way to turn it off.
There are digital controls for damned near everything, and security is universally disturbingly bad.
Whatever you're trying to stop will already have root-kitted your systems (and quite possibly have replicated) by the time you realise that it's even beginning to become a problem.
You could only shut it down if there's a choke point accessible without electronic intervention, and you'd need to reach it without electronic intervention, and do so without communicating your intent.
Yes, that's all highly highly improbable - but you seem to believe that you can just turn off the Genie, when he's already seen you coming and is having none of it.