Domain experts reach consensus and their recommendations aren’t followed in a lot of disciplines. I agree in this case it makes economic sense to stop farm subsidies — which could result in lower domestic food production and greater imports from abroad. And when the world economy is humming along smoothly that’s great. But if there’s a hiccup in the world economy —- e.g., in the case of war in a place where it makes economic sense to grow a lot of wheat or a problem in the logistics network shuttling things from where they’re produced to where they’re consumed then it’s not as clear-cut.

My naive view of politics, when they’re running well, is to navigate conflicting priorities from groups, including domain experts, the populace, etc.

And I think the farm subsidies could be interpreted to involve national security concerns on top of then economic concerns. If a world war breaks out and we’re on the opposite side from places we normally source our food then they have leverage over us.

TL/DR I think there’s more at play than just the economic concern.