Here's the population numbers for the Gruin, the great pain in the backside of the Republic.
|The Map of the Republic|
|Republic Population Numbers|
|Gruin Population Numbers|
The Eastern Cluster is seeing incursions, but they still outnumber the Gruin by about 13:1. The situation in the Far Crossing is worse, as they only have a 6:1 advantage in numbers.
The Gruin threat to the Republic then, is twofold.
1) The incursions of the Gruin themselves into the Eastern Cluster is drawing material and manpower away from the actions against the Fallen and Colserans in the Western Cluster and the Western Expanse.
2) The incursions of the Gruin threaten to eventually cut off the Western Republic and the Eastern Bridge holdings from the Far Crossing. This would block off the Republic-proper from the Rhone Cluster, which is the only practical avenue of expansion that the Republic has left. They can't expand westward because of the Fallen/Colseran situation and they can't expand south through the NOVA crossing due to interference from a to-be-described-later alien (as in utterly alien) power there.
But at the same time, the Republic is already at its limits militarily dealing with existing Colseran/Genii/Fallen/Turid threats. It just doesn't have the manpower to properly beat back the Gruin, and they still have no idea what the Vorra are, or how to interfere with their seduction of vulnerable humans into their sway.
But... The Eastern Republic grumbles that they could raise more manpower in the coming years if they abandoned certain aspects of The Way, which limit population growth, resource expenditures, and especially potentially useful technologies. Which puts them directly at odds with the Church, who maintain that these strictures have served humanity for over five thousand years, and that everyone should trust, through faith, that a Way-compatible solution to the Gruin problem will one day be found.