Sure it does. The goal is keep the farmland available and productive along with keeping agricultural infrastructure. The USA helped win WW2 because our car factory lines were retooled to make war machines.
There’s a reasonable argument for having a food stockpile in case of emergencies, but extra farmland is harder to justify.
The point of extra farmland is to make up for some expected shortfall, but you’re better off stockpiling food during productive periods than have reserve capacity for use when something else is going wrong.
PS: It is common to have quite large stockpiles of food. Many crops come in once a year and then get used up over that year. But that assumes a 1:1 match between production and consumption, a little extra production = quite a large surplus in a year.
The US’s domestic demand for food is vastly below the actual production, exports and biofuels need not be maintained in a war.