Well not surprising if 1 country has materials all others need, rather than negotiate to give up so much land they would go to war, even more so since they think they are the culprit.
I also don't know why the MC thinks going to war would be counterproductive. The opposite, historically war has been a very common way to deal with famine. Countries figure that if people are gonna die anyways, use them o grab resources of the other country. And the more die, the less mouths there are to feed.