In comparison to conquering human kingdoms, which might lead to entrapment, attacking different races is much more comfortable. No one will care about the means employed or how ungraceful the process looks.
The Dwarf Race that Blake is targeting is undoubtedly a fat piece of meat. By monopolizing the trade of high-end weaponry, the Dwarf Kingdom has amassed substantial wealth.
The current issue to consider is this: the military power of the Dwarf Kingdom is robust, and the Clergy doesn't share borders with them. Initiating a war would require cooperation from others.
However, this isn't something Blake needs to concern himself with. After successive failures in political maneuvering, his only chance of turning things around is on the battlefield.
Fortuitously, the Judgement Knights are one of the strongest forces within the Clergy. Compared to the political chess game, war is their specialty.