Coincidently, my late Dad would have been 100 today Feb1st. He joined the Terras at 16 to make sure he was amongst the first to be called up and spent 8 years in the infantry, ending up in Germany in charge of food parcels for the starving German civilians at war's end. Nearly all his mates were killed during the hostilities and he wore the guilt of survival until his last breath.
We can have no idea what that is like except from afar.