Can NATO just say enough is enough? Attacking food storage will have as large of an effect as the use of a nuclear weapon. The loss in food supply, in theory, would be directly responsible for tens of thousands of starvation related deaths.
1 nuke is launched, there's a VERY good chance every single nuke on Earth is launched. Literally everyone dies in that scenario. I agree, attacking the grainaries is evil, but it's several orders of magnitude less severe than a nuclear bomb. For instance, the 2 nukes dropped on Japan killed almost a quarter million people. Modern nuclear bombs are tens of times more powerful than Fat Man and Little Boy.
What will be interesting to watch is how it affects food prices in countries that didn't import grain from Ukraine in the first place (like the US). I'm guessing there will still be a significant effect.
Wheat prices were up 77¢ according to a friend looking at fields that haven't been contracted yet. That's just this morning. Don't know if they continued to rise or if they plateaued, but that's what the response was in the Midwest.
The US is literally a world away with huge resources of their own.
It's North Africa and Arabia that are going to bear the brunt of it, and Europe too to a lesser extent (they at least have more access to the Atlantic).
With the insane rate of increases in food prices lately, not just caused by this war, but also through cascading climate events, it was already very likely that there will be famine in at least some parts of the world. This only further exacerbates what is already a fragile situation globally. We may very well see significant global unrest and possible regime changes across the globe.