Re: Air gapping won't help you because.....a non airgapped system is insecure
Hang a sign on the air-gapped system.
WARNING:
This system is high-security and MUST NOT be connected to any wired, wireless or any other form of network. ATTEMPTING TO DO DO WILL BE CONSIDERED GROSS MISCONDUCT AND GROUNDS FOR INSTANT DISMISSAL AND MAY ALSO RESULT IN CRIMINAL PROSECUTION
You may need to change employee's contracts to allow the above to actually be enforceable, but in any security system, the technological solution (firewalls, airgapping, etc) are only part of the solution. Making sure the system's users don't do anything stupid is a part of security as well.