Fun Fact! Soldiers during the Civil War often boiled their hard tack in their morning coffee, both to soften it (as it was often hard as wood), and to boil out the worms and weevils that worked their way in! How lovely!
Tasting History with Max Miller on YouTube has a video where he recreates a US Civil War soldier's meal, and it was basically a pan fry of some sort with bacon grease and hard tack (he also has a video where he makes hard tack, and he uses some in the CW video).
Hard tack wasn't really meant to be eaten like bread, you were supposed to wet/cook it down to soften it and make it more palatable (and, well, to kill the bugs).
I was privileged enough to taste this stuff at a civil war reenactment! It's not bad! I'm sure it would get old having to live off of it, but as a random snack it was pretty edifying.
lmao, I have relatives who were in the military in the 90s and they swear to me that the crackers in the MREs back then tasted exactly like attic dust, and there's no proof that they weren't made of just that