I'm not sure how the military devices help understand those numbers much. Presumably, the idea is to take something whose impact is large and intuitively understood and identify it with the price, so that other things which are nonintuitive with similarly large prices can be understood. (My preferred version of this is "$1M is about the life's work of a median American", in the sense of being the median salary over a lifetime minus what a human needs to survive. $1M is a lot of money, but I can kind of imagine what a man can build in his life.)

But military devices seem like things whose value is very unintuitive. (I've made similar criticism of people who say "oh, $6B? That's just three B2 bombers.") Obviously, we have no real conception of how complicated and expensive such devices are to build. But more importantly, few of us have a good grasp of the value to world stability delivered by rarely-used weapons that play a mostly deterrent role.