The one thing WW1 taught even casual observers is that a modern industrial nation can sustain a war and war production until they start running out of bodies.
Contemporary material demands are a bit more hard to supply but the basic functionality of an army is still basically the same, you give enough guys rifles, boots, and helmets and things will tend to work out.
When the war ends, I expect they’ll reduce military cost dramatically, because they have to.
Wishful thinking
The one thing WW1 taught even casual observers is that a modern industrial nation can sustain a war and war production until they start running out of bodies.
Contemporary material demands are a bit more hard to supply but the basic functionality of an army is still basically the same, you give enough guys rifles, boots, and helmets and things will tend to work out.