There are other novel means to leap air gaps. I remember from a few years ago a technique using ultrasonic by, IIRC, spinning a harddrive at certain intervals a

There are other novel means to leap air gaps. I remember from a few years ago a technique using ultrasonic by, IIRC, spinning a harddrive at certain intervals and listening in from a standard PC mic. Also, a stripped down computer like you describe is going to be of marginal utility. How do you get the sensitive data in or out? Transcribe by hand? Might as well write your secrets in a code on a piece of paper and lock it in a vault. Airgapping by removing CD/USB/network, you arent really increasing security. Youre just freezing the machine in a point in time with no security updates or other useful means of actually handling sensitive materials. One could argue this actually makes it easier to exploit given sufficient physical access. Also, NSA using keyloggers doesn't make them best of the best (not that they arent good at what they do, just saying key loggers is a small barrier and very common and easy to use - easy enough I was using them as a kid in the 80s). They may have superior ways of achieving it, such as supply chain attacks, but key loggers have been around pretty much since computers have existed.