Gallia, if you've read, wants to take revenge on the Alliance because of that "leaving-behind". We're trying to restore the Alliance here, uniting the Houses, but Gallia wants to destroy it, so why shouldn't we attack them? While the other houses have between wars the Gallia tries to destroy all houses (old Alliance). Also I've mentioned the Council btw, so ye we'll see how Gallia would turn out, first things first, the 5 houses most important once. Our group would have to wait how the Council advances, we might aid em too, so once Gallia would be fallen under the Council, than we can talk about involving them in this.