The War Plan is the basis of War Command. [Changed this from Command of War for simplicity - Bernd]
It has four parts: political, economical, social, and military. These are need to be in perfect harmony, but the first three are needed to be tuned to maximize the profit of the fourth.
Political part is a clear sighted, correctly judging, quick acting diplomacy.
THe economical part, is the behaviour of the nation manifesting in the tenaciously working labourers, peasants, and intellectuals. [It seemed this was written in more moral sense, than material. So it wasn't really about production of stuff, but the steadfastness of the workforce.]
The social part is the clear/pure war goal and it's necessity. [Again more like morality than preciseness. - Bernd]
These three runs before the military and plows the soil of conquest first. If there was no "pre-plow" [he literally calls it like that - Bernd], or it was done shoddy, the military has to pay for it with shedding its blood in vain.
As Napoleon said the Commander wins who makes the least mistakes and exploits best the mistakes of his opponents. [In this case, the mistakes in the pre-plow. - Bernd]

Picrel I think is an example of diplomatic failure. Central Powers not just lost Italy's support, but let the Entente snatch her, and turn against them.