Why we need to test nuclear weapons

President Barack Obama made history last month when he presided over the nuclear nonproliferation summit at the United Nations Security Council. Since nuclear proliferation is among the most pressing threats facing the world, one would have thought that the president would use the Sept. 24 summit to condemn the newly discovered uranium enrichment facility in Qom, Iran.

He did not. Instead he asked the Security Council to pass a nonbinding resolution stressing the urgency of global disarmament and arms-control treaties among the five permanent Security Council members. The resolution never mentioned Iran or North Korea.

Mr. Obama also said, on behalf of the U.S., that "We will move forward with the ratification of the Comprehensive Test Ban Treaty" (CTBT). This is a profound mistake, as a ban on testing nuclear weapons would jeopardize American national security. Ten years ago this month the U.S. Senate rejected the treaty, and the reasons for doing so are even stronger today.

The CTBT then, as now, does not define what it purports to ban, which is nuclear-weapons testing. This ambiguity leaves countries free to interpret the treaty (and act) as they see fit. Thus, if the U.S. ratified the treaty, it would be held to a different standard than other nations.

Another concern in 1999 was that clandestine nuclear tests could not be verified. That, too, is still the case. While the treaty has not entered into force, the world still uses the treaty’s monitoring system (the CTBT Organizations International Monitoring System) to detect nuclear-weapons tests. But even when Pyongyang declared that it would conduct a nuclear-weapons test and announced where and when it would occur, this monitoring system failed to collect necessary radioactive gases and particulates to prove that a test had occurred.

The CTBT relies on 30 of 51 nations on its executive council—most of whom are not friendly to the U.S.—to agree that an illegal test has been conducted, and then to agree to inspect the facilities of the offending country (which can still be declared off-limits by that country). This enforcement mechanism is obviously unworkable.

But there’s another defect in the CTBT. There were concerns a decade ago that the U.S. might be unable to safely and reliably maintain its own nuclear deterrent—and the nuclear umbrella that protects our allies such as Japan, Australia and South Korea —if it forever surrendered the right to test its weapons. Those concerns over aging and reliability have only grown. Last year, Paul Robinson, chairman emeritus of Sandia National Laboratory, testified before Congress that the reliability of U.S. nuclear weapons still cannot be guaranteed without testing them, despite more than a decade of investments in technological advancements.

Treaty proponents, nevertheless, believe the prospective benefit of ratification outweigh its risks and problems. And what, exactly, is the benefit of ratification?

Mr. Obama has said that if the U.S. ratifies the test ban treaty the world would finally get serious about the problem of proliferation, in other words, the nuclear-weapons programs of Iran and North Korea. As Secretary of State Hillary Clinton put it at the Sept. 24 nuclear nonproliferation summit at the U.N., "CTBT ratification would also encourage the international community to move forward with other essential nonproliferation steps."

There is some evidence to test that claim. Iran and North Korea are already in violation of the Nonproliferation Treaty (NPT), which requires that they do not develop nuclear weapons. Yet for years the world has been unable to agree that these nations’ NPT obligations must be enforced. If the world can’t or won’t enforce the NPT there is no reason to believe it would be any more effective in enforcing the CTBT.

Our allies have the same incentive to prevent Iran from going nuclear today as they would if the U.S. ratified the CTBT. There is nothing in the test ban treaty that enhances their incentive to stop Iran.

There’s a related theory, which is that the U.S. has to ratify the CTBT if it wants to have any credibility or leadership on nonproliferation. Assistant Secretary of State Rose Gottemoeller spoke for many in the arms-control community when she said at a nonproliferation conference in Virginia in August, "There is no step that we could take that would more effectively restore our moral leadership."

Aside from the fact that countries will act in their best interest whether or not the U.S. "leads" them, no one can legitimately question U.S. commitment on proliferation issues. No nation has worked harder than the U.S. to pressure North Korea and Iran, and there is no evidence that Russia and China would suddenly help us if we ratified the test-ban treaty.

Moreover, unlike other nations, the U.S. has not conducted a nuclear-weapons test since 1992; it has not designed a new warhead since the 1980s or built one since the 1990s. It has reduced its nuclear-weapons stockpile by 75% since the end of the Cold War and 90% since the height of the Cold War. Meanwhile, the U.S. has spent more than $7 billion on the Nunn-Lugar program, which deals with the "loose nukes" threat, and it will spend more than $2 billion on nonproliferation measures such as securing loose nuclear material this year alone. There is again no evidence one more symbolic gesture is going to change anything.

The immediate challenge we face is the threat posed by nuclear proliferation in the hands of rogue regimes. That, and not a flawed, irrelevant test ban treaty, is what the administration should focus on.

Originally published in the Wall Street Journal