Editor's note:

The United States is considering conducting nuclear testing in order to bring China and Russia to the negotiating table. Steven Pifer explains how this approach could backfire. This article was originally published by the Freeman Spogli Institute for International Studies at Stanford University.

Senior U.S. officials reportedly have discussed conducting a nuclear weapons test for the first time in 28 years.  Some apparently believe that doing so would provide leverage to persuade Russia and China to agree to Washington’s proposal for a trilateral nuclear arms negotiation.

In fact, a U.S. nuclear test would most likely have a very different effect:  opening the door for tests by other countries to develop more sophisticated nuclear weapons.  A smarter policy would maintain the current moratorium on nuclear testing, and ratify and seek to bring into force the 1996 Comprehensive Test Ban Treaty (CTBT).

Several media sources have reported that a recent Deputies Committee meeting (composed of deputy or under secretaries of the Departments of State, Defense and Energy and senior representatives from other relevant agencies such as the Joint Chiefs) discussed a “rapid [nuclear] test.”  It was suggested that this could provide leverage to press Moscow and Beijing to take up the Trump administration’s proposal for a trilateral negotiation on nuclear arms.

No consensus was reached.  Apparently, representatives from State and Energy’s National Nuclear Security Administration opposed the idea. They were correct to do so.

Beijing opposes a trilateral negotiation since the United States and Russia each have well more than ten times as many nuclear weapons as does China.  How would a U.S. nuclear test influence that calculation?

Moscow has linked a negotiation on all nuclear weapons (going beyond the deployed strategic warheads constrained by the 2010 New Strategic Arms Reduction Treaty) to U.S. readiness to address issues such as missile defense constraints, a no-go area for the Trump administration.  How would a U.S. nuclear test change that?

The more likely impact of a U.S. nuclear test would be to open the door to resumed testing by other countries.  China, which has conducted 47 nuclear tests—less than one-twentieth the number conducted by the United States—might jump at the chance to test more sophisticated weapons designs.  India and Pakistan, who each conducted a small handful of tests in 1998, could likewise consider new testing.  They could blame Washington for breaking a nuclear testing moratorium that all countries, except North Korea, have observed since 1998. (The Director of the Defense Intelligence Agency stated in May 2019 that Russia “probably is not adhering to its nuclear testing moratorium in a manner consistent with the [CTBT’s] ‘zero-yield’ standard” but backed away from that assertion in answer to a follow-up question, in which he said that Russia had the “capability” to conduct very low-yield tests.  A June 2019 U.S. statement affirmed the assessment that “Russia has conducted nuclear weapons tests that have created nuclear yield” but provided no back-up information.  Moscow heatedly denied the charge.)

Ending the moratorium would not advance U.S. security interests.  The United States has conducted about as many nuclear weapons tests as the rest of the world combined (and 30 percent more than the number conducted by the Soviet Union/Russia).  U.S. weapons scientists learned more from testing.  When I served as a diplomat at the American Embassy in Moscow in 1988, I accompanied a U.S. team to the Soviet nuclear test site at Semipalatinsk (in what is now Kazakhstan).  Our Soviet hosts showed us a vertical shaft for an upcoming underground test; it was about three feet in diameter.  A U.S. team member from the test site in Nevada, which the Soviets would visit the following month, commented that U.S.-drilled vertical shafts for nuclear tests typically were nine to eleven feet in diameter.  That maximized the area above the weapon for instruments that would gather a burst of data in the nanosecond before they vaporized.

The testing moratorium and the CTBT, if ratified and entered into force, would seem to lock in an area of U.S. advantage regarding nuclear weapons and nuclear effects.  Why would we want others to test and erode that advantage?

Up until the idea of gaining leverage with Beijing and Moscow arose, the primary possible reason for a return to testing was if it became necessary to confirm the reliability of a weapons type in the stockpile.  However, the National Nuclear Security Administration has overseen for 25 years the Stockpile Stewardship Program, intended to confirm that U.S. nuclear weapons are safe, secure and reliable without having to test them in a manner that produces a nuclear yield. To do so, the program uses supercomputers, modeling and tools such as the Dual Axis Radiographic Hydrodynamic Test Facility (think of the world’s most powerful X-ray device).

Each year, the commander of Strategic Command and the directors of the national nuclear laboratories at Los Alamos, Sandia and Lawrence Livermore certify the safety and reliability of the nuclear stockpile.  When I visited Los Alamos several years ago, the director told me that, as long as the Stockpile Stewardship Program was funded, he was confident that nuclear testing was not needed.  He added that, as a result of the program, weapons scientists had learned things about how nuclear weapons work that they did not and could not learn from testing nuclear weapons underground.

The smart thing for U.S. national interests is to continue the moratorium, ratify the CTBT, and press others to ratify so that the treaty can be brought into force.  The Senate failed to give consent to ratification in 1999, due to concerns about how to maintain the stockpile’s reliability without nuclear testing and about monitoring the treaty.  The Stockpile Stewardship Program, just in its beginning stage then, can now answer the first concern and has been doing so.

As for monitoring a test ban, U.S. national technical means have improved over the past two decades, and the Comprehensive Test Ban Treaty Organization has established the International Monitoring System with some 300 stations around the world.  It can detect underground nuclear explosions down to below one kiloton (the weapon that destroyed Hiroshima had a yield of 15 kilotons) as well as detecting tests in the atmosphere or ocean, both of which are banned by the 1963 Limited Test Ban Treaty.  Once in force, the CTBT also provides for an inspection mechanism.

As former Secretary of State George Shultz said in 2013, senators might have been correct not to consent to ratification in 1999, but given the Stockpile Stewardship Program’s development and enhanced monitoring systems, they would be right to vote for ratification now.

Conducting a nuclear test to bring China and Russia to the negotiating table will not work.  It will instead open the door for others to resume testing and close a nuclear weapons knowledge gap that favors the United States.  That will not make us safer or more secure.  It is an unwise idea that hopefully will continue to meet resistance within the U.S. government.