Not just military trucks - old diesel Mercedes-Benz sedans do this do. My next door neighbor, a Haitian car collector has -3- different diesel M-B sedans, from 77-81. All of them require leaving the key in the ignition for a good while before the car will start... part of that, I think, is letting the glow plug reach temp. The other part is the fuel pump. Man, those cars are slow but elegant.

I love how they literally diesel forever after you turn the key to "off" (they don't stop running), you have to pop the hood and press this red "Stop" button with a long branch or baseball bat or something similar!! LOL. .. be glad we have PGM-FI.