Everytime I see something like this I ask "why was this system connected to the internet in the first place". Sure an intranet only computer can be compromised

Everytime I see something like this I ask "why was this system connected to the internet in the first place". Sure an intranet only computer can be compromised as well, usb drive, social engineering, etc. but it is exponentially harder. Really hoping ICBM systems are not on the internet because some general wanted to monitor them from his smartphone.