Depends. It is easy to gauge the amount of domestic wheat consumption and then determine whether a surplus is to be had (which could be exported) or not and then frozen. If a surplus is to be had, then we look to get as much for the export with certain trade partners for things we need (like chips from Taiwan, etc) that we can get.
I believe U.S. is net exporter of wheat so as of yet it does not look like we will face nay wheat shortages but those that rely on Russia wheat imports will...
Grain harvests around the world are not expanding like they used to, some have seen significant declines recently (37% down here in Alberta, and Saskatchewan, last year). This is in "cool" La Nina years, I hate to think what we'll see when the next El Nino materializes. Anyway, it turns out leaving the Holocene is not a good idea if you want to grow a lot of grass... uhh... nm.