United States Senator Jon Kyl (R-AZ) made a compelling argument in today’s Wall Street Journal against ratifying the Comprehensive Test Ban Treaty (CTBT).  For nearly two decades the United States has relied on technical extrapolations to verify the reliability of the U.S. nuclear stockpile.  But these technical extrapolations are essentially ”best guesses” based on historical trends and data.  As I said in a recent post, “The only way to be certain a weapon is reliable is to test it.”  Kyl is right when he argues that the credibility of our nuclear deterrent is dependent on the reliability of our stockpile.  As I’ve mentioned previously, as the credibility of our deterrent decreases, friends and allies may be forced to develop their own nuclear deterrents. 

Critics argue that failure to ratify the CTBT will hinder Washington’s ability to lead global nonproliferation efforts.  Such arguments are unconvincing, however.  As Kyl notes, the U.S. has an impressive record when it comes to nonproliferation:

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.

Kyl is absolutely right.  It is clear that U.S. behavior is not the primary driver of other state’s decisions to acquire and/or proliferate nuclear weapons.  These efforts did nothing to dissuade North Korea or Iran from developing offensive nuclear weapons programs.  As I wrote in The Weekly Standard in March 2009:

It remains fashionable in liberal foreign policy circles to argue that Washington’s behavior is the main catalyst for the decision of other states to acquire nuclear weapons.  Of course, Washington’s behavior influences other states–but only to a degree. Washington’s decision to reduce the number of its operationally deployed warheads from around 6,000 to approximately 2,000 has done nothing to dissuade Pyongyang or Tehran from operating aggressive nuclear weapons programs.

Jeffrey Lewis at ArmsControlWonk rightly notes the domestic political challenges associated with a resumption of nuclear testing.  However, Lewis’s analysis is incomplete because he neglects the broader strategic issue of why we have nuclear weapons, how they are critical to U.S. national security, and the importance of credibility.  Not only does our stockpile keep us safe from a state-sponsored nuclear attack, but it also provides us with bargaining advantages in the diplomatic arena (although the Obama administration clearly doesn’t seem to grasp this concept).  It is also important to distinguish between a resumption of nuclear testing and maintaining the capabilities required to conduct a nuclear test.  Many of the scientists and engineers who possess this specialized knowledge are Baby Boomers and either have retired or will be retiring in the next few years.  It is important to make sure younger generations are developing these capabilities in the event an urgent need for testing surfaces.

Dismissing the importance of testing (and the necessity of maintaining the capabilities required to test) is not only weak analysis but it’s bad policy, too.  Let’s say we ratify the CTBT.  President Obama will certainly get praise from the Davos crowd–and perhaps another Nobel Prize.  But will North Korea suddenly see the light?  Or Iran?  This token gesture will undoubtedly score the U.S. some political points with the Davos crowd, but it’s highly unlikely that ratification of the CTBT will result in any favorable outcomes for the U.S.  It’s highly unlikely that ratification of the CTBT would finally convince Moscow and Beijing to support a real sanctions package against Iran. 

At the end of the day, how does ceding our right to test advance the U.S. national interest?