In the end, it all comes back to opportunity costs. Unless one believes that every dollar saved from the Pentagon's budget will be thrown into a huge government money hole in the New Mexico desert, the reality is that at least some—and likely most—of the taxpayers' dollars that are currently dedicated to the military could be better employed elsewhere. My preference would be for each of us to keep a bit more of the money that we earn, money that we will then choose to spend as we see fit. This new private spending would more than offset the cuts in government spending, given the government's inherent inefficiencies, dead-weight losses, etc. Yes, some workers might lose jobs in the near term, but, as Gordon Adams notes, the economy has recovered from a number of previous military build downs, which were deeper and faster than those envisioned today.
Finally, we should embrace the discipline that even modest fiscal constraints can have on our grand strategy. The most "draconian" cuts envisioned under sequestration would take the military's budget back to 2007 levels—hardly a "lean" year for the defense industry—but policymakers are likely to pay more attention to how they allocate resources if they perceive that they have less of them.
During his last few months as the Chairman of the Joint Chiefs of Staff, Adm. Mike Mullen explained that the Pentagon had forgotten how to prioritize during more than a decade of ever-rising budgets. The White House and others in the national security community have as well. I'm confident that shrinking budgets will infuse a measure of prudence and restraint that is long overdue.