One could argue nuclear bombs and MAD are the reason there hasn't been a third world war. Someone asked an engineer who designed ICBMs : How do you feel

One could argue nuclear bombs and MAD are the reason there hasn't been a third world war. Someone asked an engineer who designed ICBMs : How do you feel that things you worked on may never actually be used? He said, then I have succeeded. The purpose has always been to act as an deterrent. If my work was used, then somewhere something has failed. Off topic to neuralink, but found it interesting.