Which was kind of my point. I am not a historian of 1970's wargaming, but I think it's likely that some similar form of health tracking appeared well before auspices of using it in a roleplaying game, and I think the intent behind it was no different than the intent behind any other piece of wargame mechanics. Whether the term "hit point" was used as such or whether it worked exactly the same way isn't the point. I'd buy that D&D popularized the idea to some extent, and certainly revised and change it.
Well, there are hit points and then there are hit points, but you can see the evolution in how hit points
in D&D came about through the history of D&D. In Chainmail they were literally hit points: how many hits you could take. Regular soldier, you could take 1 hit, just like most wargame units. Hero? You could take 4 hits. Superhero? You could take 8. In OD&D we see a similar design, with a bit of added variance. Damage rolls are d6. Hit Dice are
also d6, so
on average, it was a similar situation as in Chainmail, but allowed for lucky and unlucky hits.
Hit points as we know them don't come into play until the Greyhawk supplement, when finally each class gets assigned a distinct hit die, with the result of a new die added to the total each level. This also introduced variable weapon damage, further obscuring the basic "1 hit vs. 1 HD".
This truly was an innovation in gaming, because previous to that wargames used either a 1 hit = 1 kill system, or, if you were playing something like a naval game, would use hit location. Arneson's original Blackmoor game used hit location, rather than hp, because that was generally the done thing when you didn't want 1 hit = 1 kill.