I was preparing to summarize and comment on an excellently-argued piece by Richard Betts in the latest issue of Foreign Affairs, but it would seem that Ilian Goldberg at Democracy Arsenal beat me to the punch with a great summary, so I'll try not to be overly redundant. The article argues that U.S. defense expenditures need to be "strategically solvent" and appropriately matched to reasonable and achievable international goals. He argues that the half-trillion plus dollars that we currently spend on defense is both much more than is necessary to provide basic security, and much less than is necessary to achieve global imperial dominance. Particularly in an environment of economically-burdensome public debt that grows by the minute, our current defense posture, Betts argues, makes little sense. Without going into too much detail (again, just read the article, or at least the excerpts, which I promise are worth your time), he advocates a reorientation of U.S. security policy towards increased special forces and intelligence to combat trans-national threats, coupled with the ability to mobilize superior conventional forces should we enter into the sort of environment that requires them. Thus, spending on military research and development is important, and should perhaps be increased, but the maintenance of a large army and navy in peacetime makes no sense in a post-Cold War world. The United States should maintain a technological edge over, for example, China, such that we could mobilize to defeat it if and when the threat it poses becomes real as opposed to theoretical, but we need not be perpetually and fully mobilized to fight at the drop of a hat.
For example, recent proposals to add additional divisions to the army are being treated as practical, hard-headed responses to the array of security threats the United States now faces. I have yet to hear a convincing explanation, though, as to how another armored division will help combat shadowy, trans-national terrorist groups. These additions are likely to come too late to make a difference in Iraq or Afghanistan, so I fail to see what they will accomplish, unless (perish the thought) we intend on repeating the Iraq experience any time soon. Increasing the size of our military, though, is the historically standard hedge against emerging security threats, so it is the knee-jerk response of American leaders, whatever its objective merits. National security would be improved if decision makers could lift such cognitive blinders, and commit scarce resources in a more holistic and appropriate way.
Taking a wider view, Betts's article also raises the issue of America's geopolitical standing in the 21st Century. I have argued elsewhere that the United States is likely to see it's relative power decline precipitously over the next hundred years. Though America will almost certainly remain a major player in the global system, its position will likely be akin to that of 19th Century Great Britain - the most powerful state in a group of powerful states - and unlike the hegemony that it now enjoys. The transition to an international system of "asymmetric multi-polarity," though, will not go smoothly if the United States bucks against a sensible reorientation of its global posture to reflect the increasing political and economic power of nations like China, India and Japan.