At least a massive famine could decrease the number of their vassal races. It could save us from their disgusting tactics of using beast-swarms.
Times of calamity demand more wars.
It may sound confusing, but that's the magic of politics.
If the locust plague isn't serious, the Alpha Kingdom which is still amassing power, naturally wouldn't stir up matters.
But if the calamity spreads, even threatening next year's food production, then there's no other way, let's head straight to war!
Asking for help, we can't necessarily get food from other nations. But if the Orc Empire invades from the south, none of our neighboring nations would dare to refuse providing food supplies.
As one of the strongest nations in the human world, if the Alpha Kingdom collapses, the chances of the neighboring nations withstanding the military might of the Orc Empire also wouldn't be high.