Joseph II asked with concern.
As the dominant power of the previous era, the Orcs are not only enemies of the three kingdoms, but the entire human race. When facing the enemy of the race, naturally, everyone must join force.
Theoretically, the combined forces of the three kingdoms could engage the Orcs in a fight to the death. But looking at the current situation on the battlefield proves that this theory is unrealistic in practice.
It's not that everyone isn't trying hard enough, but simply that the circumstances faced by both sides are different. The Orc army can use the corpses of their companions as military provisions, a notion too barbaric for the human army.
If all three kingdoms mobilize every force they can, even the logistical pressure alone could easily cause the frontline to collapse.