The question is whether Congress will just slash money arbitrarily, the salami-slicing that Gates fears, or whether it—and the team that Gates' presumptive successor, Leon Panetta, puts together—will restore the art of military-budget analysis.
Gates did a fair bit of this in his time. He halted the F-22 not just because it was an expensive Cold War relic but because his analysts noticed that the Air Force's justification for continuing to build more planes was deeply flawed.
At the time, the Air Force already had 183 of these planes. Its senior officers wanted to build a total of 387. Yet their case for this expansion, laid out in internal briefing books, assumed that the United States would someday fight two wars simultaneously against two foes with just as much air power as we have. It also assumed that a large percentage of the F-22s would be in routine maintenance depots when the wars started—i.e., that the two foes would coordinate a surprise attack.
The unstated implication was that if the attacks did not come as a surprise, and if we therefore had more of the F-22s online and ready to go, we wouldn't need quite so many planes to begin with. And if we were willing to let go of the premise that two comparably powerful nations (a resurgent Russia and a much more powerful China?) would go to war against us simultaneously, the 183 F-22s that we already had—in addition to the many other planes in the arsenal—would be plenty.
And so Gates stopped the project. Obama agreed, to the point where he announced he would veto the entire defense bill if it contained money for a single additional F-22. And Congress went along (with 15 Republican senators joining in), despite the fact that the Air Force had over the years ingeniously parceled out contracts and subcontracts to corporations in 44 states.
Many other weapons systems and military missions could be subjected to the same sort of analysis. For instance, the defense budget that Obama and Gates put forth in February includes $24.6 billion for 11 new ships, $4 billion for two new Virginia-class submarines, and $1 billion for a down payment on a new nuclear aircraft carrier. Are all these things really needed? What are the assumptions and scenarios that support the case? How valid are they? Do we need to spend $9.4 billion to buy 32 F-35 stealth fighter planes, when we're also spending $2 billion to upgrade the older (but still world-class) F-15s? And what about the $1.4 billion for 24 new Trident II submarine-launched ballistic missiles? Is our nuclear deterrent degraded without them?
These are the questions that Gates is saying we need to ask, even if he might disagree with the answers.