U.S. President Barack Obama, Defense Secretary Leon Panetta and Joint Chiefs of Staff Chairman General Martin Dempsey unveiled a new long-term defense strategy on Wednesday designed to save money while adapting U.S. forces to tomorrow’s security challenges.

While short on specifics about individual programs -- those will come later this month in an official budget request -- the Defense Strategic Review is realistic about trims in force size and retiree costs, and rightly calls for an increased focus on Asia and the Pacific Ocean, counterterrorism and cybersecurity.

In particular, we applaud the insistence that U.S. “deterrence goals can be achieved with a smaller nuclear force.” Unlike many other areas of the Pentagon budget, in which strategists and number crunchers should be able to negotiate their way to fiscal detente, the nuclear issue requires a complete rethinking of long-term strategy and philosophy.

Today’s world calls for a two-part nuclear strategy: ensuring that the U.S. has a robust retaliatory force against a major power (a resurgent Russia or a rising China) in a large-scale nuclear war, and maintaining a flexible deterrent to deal with regional challenges in a proliferating world (think Iran, North Korea and, perhaps, Pakistan). The key is making certain that the arsenal is optimal in terms of size, cost and, most important, capability.

Check Major Powers

The U.S. has 5,000 or so warheads (fewer than half of which are deployed at a given time), down from 31,225 during the Cold War. Under the 2010 New Start treaty, by 2018 the U.S. will be limited to 1,550 strategic warheads, most of which are on long-range ballistic missiles in U.S. silos or aboard one of 14 Ohio-class submarines. These are the high-yield Strangelovian weapons that we (and any potential enemies) know are very unlikely to be used. They are of little good against, say, North Korea, given that the radioactive fallout would endanger millions in South Korea and, depending on the winds, in Japan or China. We need only maintain enough of them to provide a check on other major powers.

There are plenty of good ideas for achieving cost savings on this front. Senator Tom Coburn, Republican of Oklahoma, has outlined a $79 billion savings plan that would include cutting the ballistic-missile submarine fleet to 11 from 14 (this could involve increasing the number of missiles per boat or warheads per missile); eliminating 200 of our estimated 500 intercontinental ballistic missiles and limiting reserves to 1,100 weapons. It’s a sensible place to start the discussion, although we think the cuts could be deeper.

The second part of the strategy involves the highly accurate, low-yield weapons now carried by bombers and some fighters. These arms are better suited -- because of their limited fallout -- to an age in which weak rogue states increasingly rely on nuclear threats. Obviously, the idea of using a tactical nuclear weapon on the battlefield is no less horrifying than employing the strategic variety, but all the same, maintaining the ability to do so is a vital check on the ambitions of a nation such as Iran. And here is where we may have to spend more rather than less, at least initially.

The nuclear-equipped B-52 fleet is creaky and the B-2 bomber’s stealth technology is becoming outdated. It’s unclear if future F-16 or next-generation F-35 jet fighters will have nuclear capability (if, indeed, the latter will ever see the light of day). Furthermore, the cruise missiles that the bombers use to deliver nuclear warheads are old and failure-prone. The easiest and quickest step would be to upgrade the cruise missiles to improve reliability and accuracy while renovating the current fleet of B-52 bombers. This would have costs, but be vastly cheaper than developing a new generation of aircraft. It is also worth devoting research dollars to improving the accuracy of submarine-borne missiles, using GPS or some other technology, to make them viable for low-yield payloads despite the enormous distances they travel.

Beyond the Pentagon

The benefits of a smarter nuclear-weapons policy will spread beyond the Pentagon. The Energy Department should be able to trim billions as well from its related spending, starting with a halt on a plutonium storage and production facility at Los Alamos National Laboratory in New Mexico.

The most controversial aspect of the review will probably be its finding that, instead of being able to fight two wars simultaneously, the U.S. will have the capacity only to carry out one major conflict while “denying the objectives of -- or imposing unacceptable costs on -- an opportunistic aggressor in a second region.” Deterrence is the key to such a strategy, and it can be best achieved with a smarter, smaller nuclear arsenal.

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