That may have been the case. It is no more.
40% of US corn production goes to ethanol. There's really nothing vitally strategic about that, other than being another government handout to the farm bloc. Another 30% of corn goes to feeding animals (cattle). We don't need to consume that much meat. Overproducing high fructose corn syrup doesn't ensure everyone has something to eat.
The farmers are complicit with all this shit going on. They brought it on themselves. Maybe they need to do their "patriotic" duty, go bankrupt, so we can get farmers who aren't such dumb shits.
Our ag exports to China were about $24 Billion in 2014; last year? $9 Billion. We have lost, as a market, the most populous country on the planet. And you're talking about strategy? Come down from the ivory tower and look and how Trump and the farmers are fucking themselves over. There is absolutely no strategy at all going on here from the Republicans.