Secretary of Defense Robert Gates’ plan to cut Pentagon waste, abuse, and redundancies by $100 billion over the next five years is both more and less radical than it may seem.

The plan, which he laid out in a detailed 25-minute press briefing this afternoon, calls for cutting spending on contractors by 30 percent over the next three years, cutting the number of headquarters and commands (and the number of generals, admirals, and staff officers to go with them), eliminating duplication in intelligence staffs, and other economies—all with an eye toward replacing the Defense Department’s “culture of endless money” with “a culture of savings and restraint.”

Much of what he wants to do seems the sort of thing somebody should have done years ago. It makes no sense that the office of the secretary of defense—which includes the various deputy, assistant, and under secretaries and their staff—has swelled by 1,000 employees in the last decade. It makes no sense that the cost of contractors has grown from 26 percent of the DoD personnel budget to 39 percent (not including the contractors in Iraq and Afghanistan). It makes no sense that the Pentagon produces 700 reports and studies a year, a task involving 1,000 contractors. It makes no sense that, in an era when senior officers from the various services plan and execute joint operations routinely, the Joint Forces Command is staffed with 2,800 full-time personnel and 3,000 contractors at an annual cost of $240 million. (One thing Gates announced today is that he’s eliminating that command.) It makes no sense that, 20 years after the end of the Cold War, a four-star general and the vast staff that goes with such a vaunted officer run the headquarters in Europe.

Yet ending these practices—as Gates announced he was doing or would fight hard to do—is guaranteed to kick up a huge political and bureaucratic storm. If Air Force generals rallied such fierce resistance against Gates’ decision to halt production of their beloved F-22 fighter plane, imagine their reaction when he moves to slash the number of generals. (There are about 950 generals and admirals across the services; Gates wants, over the next two years, to eliminate the slots for 150 of them—”at minimum,” he emphasized.)

Then again, Gates won the battle to halt the F-22. And he might win this battle as well—but for a reason that illustrates just how limited his budget reforms are

As Gates emphasized in the question-and-answer period after today’s briefing, “[t]his is not about cutting the defense budget.” It’s strictly an internal reallocation. Whatever money is saved as a result of Gates’ reforms, the services can keep it and spend it on new and more weapons systems.

Gates’ goal in this exercise is to preserve “force modernization and force structure” in the face of fiscal pressures. He sees a need to keep increasing the defense budget by 2 percent to 3 percent a year (in real terms), yet the overall budget projections call for increases of just 1 percent to 2 percent. “Therefore,” he said in his briefing, “in order to preclude reductions in the military capabilities America needs,” for today and in the future, “that spending difference will need to be made up elsewhere in the department.”

In other words, his hope is that the Joint Chiefs of Staff might be willing to sacrifice their perks and prerogatives if it means they’ll have enough money to buy another submarine, combat vehicle, or long-range bomber.

He hopes Congress might relax its inclination to treat the defense budget as a barrel of pork, out of the same reasoning. Yes, as Gates put it, junking the Joint Forces Command will upset the congressional delegation from Virginia (where the command is based). But maybe the legislators will buy in to the idea if they see that saving all that money will mean the Navy can build another submarine in Virginia’s Norfolk shipyard.

It’s a tough sell, politically. There is a reason no previous defense secretary has made a run against these kinds of entities: They’re protected by an interlocking web of officers, bureaucrats, corporations, and legislators, all of whom have an interest in their survival.

Gates is canny to play off one set of interests against another (drop the Joint Forces Command, pick up another ship; give up a dozen generals, win a few more of those armored vehicles you’ve been eyeing). Maybe it will work. But by notching up his victories in this manner, he forgoes a path that would have yielded much greater savings.

The big money and the real savings lie precisely in the “force structure” and “force modernization” that Gates is aiming—and genuinely wants—to protect. In the question-and-answer period, he said that about half of the weapons-procurement budget goes for modernization—that is, for building new weapons, most of which have little or nothing to do with the wars we’re fighting in Iraq and Afghanistan. Since the current budget ($549 billion, not counting the costs of our two wars) contains $137.5 billion for procurement, that amounts to roughly $70 billion.

Gates wants the Pentagon and the military branches to conduct a “clean-sheet review” and to “start setting priorities, making real tradeoffs, and separating appetites from real requirements” when it comes to things like contractors, headquarters, overhead, and so forth. And that’s all to the good. But he’s not launching any similar campaign when it comes to deployments and weapons systems. (In fairness, last year, he did cut about 20 weapons programs, including the F-22—more than any defense secretary in 40 years. But budget officials estimate that the bag of goodies is still bursting way beyond our ability to pay for them.)

The steps Gates took today have far-reaching implications; I don’t mean to minimize them. But there are other issues and questions that tap more deeply into the foundations of what he himself calls our “cumbersome and top-heavy” military, which has “grown accustomed to operating with little consideration to cost.”

For instance: How many submarines and aircraft carriers does the Navy really need? And do all those carriers need the same number of aircraft and escort ships? How many fighter planes does the Air Force really need? How many brigades does the Army really need?

Gates’ new reforms are based on two premises: First, that the nation can’t afford unceasing growth in the defense budget; second, that the nation can afford moderate growth in the defense budget, as long as the Pentagon shows good faith by slashing what any objective observer would label “waste.”

The first premise is unassailable, the second probably too optimistic. The fact is, we can’t afford growth in the defense budget, period. To get the cuts he’s after, Gates—as a matter of political realism—has to leave the rest of the budget alone. But at some point, some secretary of defense is going to have to open it all up to scrutiny.

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