She knew it might happen because the situation between the two kingdoms were not good after they found out about the mine's existence. Coupled with the few other trades that was siding more with the Sand Kingdom, conflicts would be inevitable.
Aurora herself was confident that the Sand Kingdom would not start any war if she was the one in charge because she knew other things that the Sand Kingdom valued and needed more than the mine.
But Queen Ella and Prime Minister Lat didn't know.
Since that was the case, they had to use the simplest method to solve the problem, which was through direct fight like this.
It was indeed the simplest method.
But it was also the method that would cost them the most. From manpower to other resources that they would use during the war, there was a large amount of it and it wouldn't be easy for them to solve the problem without wasting a lot of these important resources.
Aurora disliked the war.