It is well known that miners used to take canaries into the mine shafts as an early warning signal that carbon monoxide levels were getting to high. If the canaries died, it was time to high tail it out of the shaft.
I want to suggest that the wolf plays a similar role. It is often said that wolves ought to be preserved because of their intrinsic value, their beauty, uniqueness and the added sense of wildness that they bring to the American backcountry. It is also often said that wolves, as keystone predators, play an essential role in the long term stability of the ecosystems to which they are native.
I don't entirely disagree with either of these claims. However, I think that in addition, the wolf is a marker of the quality of our society in much the way that the canary was a marker of the quality of the air. Wolves require huge, largely unfragmented tracts of land in order to thrive without undue conflict with developed regions. They are a potential threat (albeit a very, very small threat) to our personal survival. They oblige us to take on the costs of their presence in terms of depredation, management, accomodation around human habitation, etc.
For these reasons and others, the wolf represents a non-negligible cost to human beings. Consequently, the fact that a society tolerates or fails to tolerate the continued co-existence of the wolf is a partial measure of that society's attitudes toward nature and its level of commitment to the preservation of wilderness. In this sense, the wolf is a measure of a society's magnanimity, broad-mindedness and humility; that is, it is a measure of the collective maturity and/or nobility of the society. And since these are surely the sorts of characteristic one would desire in one's society, the wolf is a measure of how desirable our society in fact is.