Over at Tapped, Robert Farley responds to my earlier fear that having an even bigger military would cause the U.S. to adopt an even more hawkish foreign policy agenda. He's not convinced:

More generally, I just don't care for the argument that we ought to structure our military around the fear that a government will use it unwisely rather than around a careful analysis of national values and interest.

As an empirical question, I'm not sure there are any good examples of "wagging" in the sense that having military capabilities caused a state to eschew a better diplomatic option in anything but the most obvious sense. The development of military capabilities follows aggressive intent, not the other way around.

Okay. At the same time, though, much of the military's force structure wasn't put in place because someone in the Pentagon laid out specific foreign policy goals and then Congress judiciously decided what capabilities the military would need in order to pursue those goals. Much of the military was put together to address needs or goals or vague threats that might arise in the future. And many weapons systems were built because Lockheed Martin wanted more money and so decided to lobby the head of the appropriations committee to finance various new projects. Here's one example.

So lots of things—militarism, defense contractors, members of Congress who want to preserve bases or arms manufacturing plants in their districts—put upward pressure on the size of the United States armed forces. You don't get enough nukes to destroy the world a dozen times over and a military the size of the next 14 countries combined through a "careful analysis of national values and interest" alone. Now, as that outsized military grows and grows, I wouldn't be surprised if Pentagon planners take a look at all the new tools at their disposal and decide that maybe now some additional foreign policy pursuits might also be feasible. I doubt it's always a straightforward process, but here's one example.

Currently, there's much debate over whether China will pose a strategic threat in the future. Many experts say it won't. Nevertheless, the Navy and the Air Force, both of which need to justify their massive budgets, are consistently pushing the direst possible assessment of China's military capabilities. Now I don't think that high-ranking officials are consciously overstating the threat to fend off budget cuts. But let's say some mid-level strategist puts together a Power Point presentation showing that China will wreak havoc in 2015 unless the United States keeps a whole bunch of warships around as deterrence. I'd imagine this presentation will garner much more attention than one arguing that China is unlikely to pursue an aggressive foreign policy and the Navy probably has too many ships. And so the China hawks slowly gain sway.

In this case, the U.S. military's force structure isn't the only thing driving its foreign policy, but the two are interconnected, and there are elements of tail-wagging at work. Meanwhile, Chalmers Johnson's book, The Sorrows of Empire, argues that America's far-flung military bases have become self-sustaining enterprises that in turn often justify further interventions in those regions. I wasn't totally persuaded by Johnson's case, at least not as stated, but that's another tail-wagging-the-dog argument if anyone's interested.