In that case calling for war makes sense… if you don’t have the food to feed your populace, have no ability to make or trade for it, the only way to survive is to eat the land, resources, population, and food of your neighbours. Aka the reason for effectively all wars from prehistory to today.
I agree with your point. They really do have to start acquiring food fast and fastest way to get them is through conquest. Though the whole premise seems lacking.
For example, waging war is very expensive. I reckon the soldiers here are professionals, because they seem like a standing force and like I said, there were no territories to pull levies from. So they'd have to be paid. Money should be tight since there's no trade, so assuming they have reserves and running on deficit for the duration of the war.
This does not eliminate the need for the soldiers to eat, on which existing supply lines, that should have been managed by the city state, is practically non existent. No army march on empty stomach. And when the armies are dissatisfied, more often swords point up to the monarch's neck. But maybe they could source food from the allied nation?
This is my point of "isekaid with no refrigeration" comes from. For societies without efficient food preservation, local production of food is only as much as a local area can consume. Thered be surplus for trade but this won't be much since veggies spoil in maybe within a week so surplus production would not be like food trade in the modern sense as they would spoil quickly.
Lets say they got the money and the food for now. Then what. They haven't ascertained enemy size and power before declaring because Boohoo good nation is opressed by evil. Even up to age of cannons and gunpowder, months even years long siege is the norm. Their money may last but food stores sure won't.
Let's say there's no siege and they duked it out Shonen manga style and the whole shebang. Only way their city would survive is to displace/murder the amount of population, enemy or otherwise, so that local food supply is capable of supporting alchimaira's population, which if their words are to be trusted, a great nation which would eclipse the local nations. Such city will have population on the millions.
That's why I personally disdain modern manga. But keep reading them anyway as I think of western comics even less.
So long story short, things have been very different since I stopped drinking 3 weeks ago so I start arguments with strangers online. I respect your opinion but I heartfully disagree.
And I'm sorry.
Peace.