@GossiTheDog Let me ask a different but important bit of the question. What's the difference. Wiping a server or blowing it to bits have the same effect. Taking out a power station by destroying the control systems electronically or by dropping wire wool on it has the same effect ? Is an attack that causes a control system to physically detonate a device physical or cyber-attack.
I don't think viewing them as two worlds works. If anything they are parts of one attacking system.