Guest-blogging for Stephen Walt last week, I offered some criticism of Stephen Brooks and William Wohlforth’s book, World Out of Balance. Brooks has emailed to offer his response, which I post below with my reply.

Brooks writes:

First, the concluding chapter of our book distinguishes between two forms of systemic activism that a leading state can pursue — the first one relies on the use of the military and the second (identified by Robert Gilpin) involves changing the structure of the global economy, international institutions, and standards of legitimacy. We favor a focus on the second approach to systemic activism (that is what our Foreign Affairs article is all about) and taking this route does not involve the deployment or use of military force. It is hard for me to see how undertaking this second form of systemic activism can contribute to imperial overstretch.

Second, our main point about the financial crisis does not concern the US policy response. Rather, the essential point is that the crisis does not change the fact that America’s lead over its competitors is very, very large and that relative power shifts slowly. Knowing that the US is so far ahead is sufficient for us to reach the conclusion that the US will long remain the sole superpower.

My response is as follows:

Let me start by making clear that I think Brooks and Wohlforth have the better of the “is unipolarity ending?” argument. I also think they have the better of the argument about the likely implications of the financial crisis on the balance of power. Due to interdependence and a number of other factors, the United States will almost certainly emerge from the wreckage with its unipolar status intact.

Rather, the point of my highlighting their argument that the long-term fiscal problems in the United States “can be fixed” was to observe that they seem quick to dismiss problems that may pose serious danger to America’s standing over the medium term. To my mind, the fiscal imbalances are significant, and don’t appear likely to be fixed any time soon.

Second, Brooks adds that his and Wohlforth’s preferred systemic activism does not involve military activism, but rather a focus on “changing the structure of the global economy, international institutions, and standards of legitimacy.” On this point they cite Robert Gilpin. Gilpin did distinguish between three objects of foreign policy (physical/​military control of territory, “influence over the behavior of other states,” and influence over the world economy), and acknowledged that economic control had increased in salience since the global economy developed. But he made clear that economic interests “cannot be easily isolated from the first two” types of objective. That is, the relative weight of the three may shift, but they remain tethered to one another.

To my mind, this fact can be seen in Brooks and Wohlforth’s proposal in Foreign Affairs to revise the nuclear Nonproliferation Treaty. While the authors present this as an institutional change, it would create laws that would need to be enforced. For the past couple decades, as a unipole, the United States has tasked itself with being the ultimate backstop against proliferation, with mixed results. At bottom, then, the question is who will enforce the law?

The authors propose creating an institution to provide nuclear aspirants with LEU but precluding them from obtaining indigenous enrichment capabilities, and creating a new institution involving NATO allies, South Korea, Japan, and Australia to impose sanctions on the violators of this new regime. If recent experience is any indication, though, the countries listed do not believe it in their interests to impose tight economic sanctions, let alone military action, to stop proliferation. One wonders how the creation of a new institution would shift these countries’ willingness to impose binding constraints on proliferation.

A primacy strategy that focuses on enhancing legitimacy and international institutions does not seem separable from military power—and the willingness to use it. If Brooks and Wohlforth’s position is that the systemic activism which they favor does not involve “the deployment or use of military force,” then that is a curious view indeed.