According to an 86 year bud of mine who served in a Special Forces base, Phu Tuc Vietnam in the early 1960's, "at one time every Infantry Officer had a Randall".
These are mine, purchased them at Randall in Orlando
Back in the 1960's, we did not have as many choices in heavy duty knives as we do now. Compared with Western, Case, Boker, etc, a Randall was a heavy duty knife. Compared to military knives, a Randall was an advanced design. We also did not have the internet, you received your knife information word of mouth, or through ads in magazines.
this is earlier, but a typical ad. One model is being advertised.
If you wanted to know more, you sent money for a catalog.
Now we have many more, and good choices. At one time these were carried in PX's
These knives are relatively cheap. And they are good designs, and hold up. When you are talking enlisted, they don't make that much, and losing a $500 Randall Model 1, would be a large financial loss. A Afghan war bud of mine was looking for "throw away" knives. When he was blown up, not all his equipment made it back with him to base. He had Aladdin Thermos he missed as he carried it for a number of tours. It was beat to hell, had been run over by a MRAP, and yet held its vacuum. I had a picture of it, and he asked me to send that picture to him, so he could ask his buds in Afghan, if anyone had his thermos.
Bud also mentioned, he did not need super hard steels as he could not sharpen the knife in theater. He had sent one back to the manufacturer to get resharpened. This is what he could get out of supply as a sharpening stone:
Now really, what do you think you are going to do with a "combat knife" in a modern industrial war? You going to jump 3000 feet in the air and stab a drone? (that drone will see you before you see it, and give you a surprise present) Going to sneak up on someone who has night vision, and a fully automatic weapon, and cut their throat? That's movie stuff.