Anatol Lieven has the best of the argument:
Signer compares America’s role in the world to the quarterback of a football team: "He leads by example, but it’s the team that wins the game." One might say that Signer’s choice of sporting metaphor exposes the limits of his entire philosophy–because, of course, far from leading the world in American football, the United States is more or less the only country in the world that plays the sport. Moreover, this entire metaphor is–to put it mildly–inappropriate. The whole point of team games is that the central purpose and the governing rules do not have to be debated and cannot be opposed: They are laid down a priori. If this were the case in international affairs, things would certainly be simpler, but this is unlikely to happen any time soon. Second, if the quarterback repeatedly flounders, he is removed by his coach, and if he repeatedly breaks the rules, he is banned by the authorities. Signer’s America, by contrast, is the permanent quarterback, by its own decision and some kind of divine right.By contrast one can't help but feel that Signer has missed Anatol's point, as a couple of his commenters point out.
I see that Anatol has a new book out; I know him fairly well and I know his co-author slightly (he's the one on the right). Must look out for that.