This is actually a massive undertaking. An undergraduate at MIT taking a semester-long course on this will barely scratch the surface of it. Furthermore, you're never going to suddenly and unexpectedly need to know this. Any situation where you plan an invasion is going to be preceded by spending a long time getting into the position where people trust you with their lives and the fates of their nation.
> die gallantly
You're only ever going to be in this situation once, and probably not even that. Why does it matter how gallant your heart attack is?
These skills make a bit more sense in a world where most of us need to march off to war. Happily, we don't live in that world.
You should prepare for the situations you are only mildly unlikely to be in and where your skill matters.
It's literature, and SF, so it would be a mistake to take the quotation too literally. But since we're here; the thing to remember about Heinlein is that he was a romantic and a futurist at the same time. Hence his militarism wasn't so much about the enemy as about providing an opportunity for romantic heroism. Similarly with the other items in the list. It's not grounded in practical necessity but in a "renaissance man" / hero of a novel approach to being able to not just handle situations but show off in them.
>These skills make a bit more sense in a world where most of us need to march off to war. Happily, we don't live in that world.
Depends how old you are.. some historians are keen to point out that the global climate is very similar to the conditions just before WW1. Will you be of conscription age if WW3 does break out in the next decade?
> You're only ever going to be in this situation once, and probably not even that. Why does it matter how gallant your heart attack is?
I think doesn't exactly refer to the act of dying, but is more along the lines of "The object of war is not to die for your country but to make the other bastard die for his." So don't exactly want to die; rather, you want to avoid it, but should it happen, you just want to make it very expensive.
But of course, it could also have nothing to do with war; it could be about how you face death, and how much of a burden you leave to your loved ones. (E.g. don't commit suicide leaving a note that tries to shift the blame to your family, or whatever).
As others have pointed out, Heinlein was writing literature, not management or career advice. That said, planning a modern, distributed web service probably isn't far off in complexity from the invasions he would have been picturing.
As for dying gallantly... you're right that we'll all face it only once. Some go bitterly, some go cravenly, some 'rage against the dying of the light'. I'd say part of a life well lived is to face its end with brave, 'gallant', acceptance, whatever circumstance precipitates that end.
> Plan an invasion
This is actually a massive undertaking. An undergraduate at MIT taking a semester-long course on this will barely scratch the surface of it. Furthermore, you're never going to suddenly and unexpectedly need to know this. Any situation where you plan an invasion is going to be preceded by spending a long time getting into the position where people trust you with their lives and the fates of their nation.
> die gallantly
You're only ever going to be in this situation once, and probably not even that. Why does it matter how gallant your heart attack is?
These skills make a bit more sense in a world where most of us need to march off to war. Happily, we don't live in that world.
You should prepare for the situations you are only mildly unlikely to be in and where your skill matters.