from Politics, Power, and Preventive Action and Center for Preventive Action

An Iranian Nuclear Weapon: How Would We Know?

February 07, 2012

The late North Korean leader Kim Jong-il waves to crowds in April 1992 (Courtesy Reuters/KCNA).
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As President Obama articulated in his State of the Union address, the goal of U.S. policy toward Iran is clear: “To prevent Iran from getting a nuclear weapon.” There are a number of problems inherent to this objective, however. How do you operationalize it? How would you know that Iran has produced a nuclear weapon, or is nearing the completion of one?

From recent history in North Korea, we know of five distinct steps on the spectrum toward becoming a nuclear weapons state.

1. The U.S. Intelligence Community (IC) estimates that North Korea has sufficient weapons-grade fissile material to build a nuclear weapon.

In 1989, North Korea shut down its 5 megawatt graphite-moderated reactor at Yongbyon and removed the nuclear fuel rods, which were reprocessed into plutonium in March 1990. However, the full extent of North Korea’s deception regarding spent fuel removal and reprocessing as well as its plutonium cache was unknown until the release of IAEA environmental measurements in 1991. In November 1993, the CIA briefed President Bill Clinton that North Korea has a “better than ever” chance of possessing enough plutonium for one or two nuclear weapons,” based on estimates of the maximum it could have produced during the shutdown. (Today, North Korea possesses between six to ten bombs worth of plutonium.)

2. The U.S. IC estimates that North Korea has a weapon.

In April 2001, Deputy Director for Central Intelligence John McLaughlin stated, “ North [Korea] probably has one or two nuclear bombs.” It is important to note that this belief was not based on a nuclear test.  In August 2001, in an unclassified response to questions from the Senate Select Committee on Intelligence, the CIA revealed: “North Korea has produced one or two simple fission-type nuclear weapons and has validated the designs without conducting yield-producing nuclear tests.”

3. North Korea informs U.S. officials that it possesses a nuclear weapon.

In December 2002, North Korea removed the metal seals and disabled the fifteen surveillance cameras installed by the IAEA at the Yongbyon nuclear reactor and reprocessing facility. On December 31, 2002, the final two IAEA inspectors (both Russians) in North Korea were forced to leave the country. In April 2003, North Korean negotiators disclosed to U.S. diplomats that they possessed nuclear weapons and had reprocessed all of the spent fuel previously frozen under the 1994 Agreed Framework. In February 2005, in its most definitive public statement to date, the North Korean foreign ministry stated that the country had indeed “produced nuclear weapons.”

4. North Korea conducts a verifiable nuclear test.

On October 9, 2006, North Korea conducted an underground nuclear test, which it claimed was “conducted with indigenous wisdom and technology 100 percent” and created a “powerful self-reliant defence capability.” One week after the test, the Office of the Director of Intelligence (ODNI) released a statement affirming North Korea’s nuclear progress: “Analysis of air samples collected on October 11, 2006, detected radioactive debris which confirms that North Korea conducted an underground nuclear explosion…The explosion yield was less than a kiloton.” After claims of a second test in May 2009, the ODNI assessed, “North Korea probably conducted an underground nuclear explosion…The explosion yield was approximately a few kilotons.”

5. North Korea has a verifiable nuclear delivery vehicle.

North Korea could attempt to covertly transport a nuclear weapon aboard an airplane, ship, submarine, or ground vehicle, although all are probably too unreliable to successfully deliver such a highly-valued weapon. If there were a crisis, however, North Korea could decide to rush a bomb onto one of those platforms, much as Israel quickly assembled nuclear weapons to be delivered by plane on the eve of the Six Day War in 1967. According to the National Intelligence Council in 2001, the more plausible delivery method is ballistic missiles: “Missiles provide a level of prestige, coercive diplomacy, and deterrence that nonmissile means do not.”

In an unclassified report to Congress in August 2007, the ODNI stated, “North Korea has short- and medium-range missiles that could be fitted with nuclear weapons, but we do not know whether it has in fact done so.” In January 2011, Secretary of Defense Robert Gates warned that within five years North Korea could develop the capability of striking the U.S. homeland with an inter-continental ballistic missile (ICBM), presumably with the Taepodong-II missile, which failed in flight tests in July 2006 and April 2009. (Various Pentagon officials have acknowledged that the thirty ground-based missile defense interceptors deployed in Fort Greely, Alaska, and Vandenberg Air Force Base, California, will be capable of intercepting a North Korean—or Iranian—missile “for some years to come.")

In the case of Iran, the U.S. IC does not believe that Iran has reached any of the five steps along the nuclear weapons spectrum. Moreover, as the Director of National Intelligence James Clapper affirmed last week in a Senate hearing, “we don’t believe they’ve actually made the decision to go ahead with a nuclear weapon.” However, if Iran fulfills any of the five steps, it could spell failure for the Obama administration’s strategy to prevent Iran from becoming a nuclear weapons state. Prior to these steps are a series of “red lines;” policymakers and analysts continue to guess what specific Iranian actions would trigger a military response by the United States. In an upcoming post, I will tackle the question of red lines, and what could compel a preemptive attack against the Iranian nuclear program.