One major and poorly explained reason for the invasion of Iraq was not the the physical presence of WMD but the willingness of a state with WMD capability and/or weapons to train and equip terrorists and possibly provide them with said weapons. While little serious diplomacy had been attempted with Iran and North Korea, Iraq showed itself time and again unwilling to cooperate. Additionally, it actively maintained WMD programs and was trying to both undermine and get the sanctions against it lifted.
The nexus between terror networks and rogue states is an issue poorly explained by the right and poorly understood by the left. Today’s further revelations about the A.Q. Khan network highlight why this is a very serious and very real threat. The Washington Post reports that
An international smuggling ring that sold bomb-related parts to Libya, Iran and North Korea also managed to acquire blueprints for an advanced nuclear weapon, according to a draft report by a former top U.N. arms inspector that suggests the plans could have been shared secretly with any number of countries or rogue groups.[...] The A.Q. Khan smuggling ring was previously known to have provided Libya with design information for a nuclear bomb. But the blueprints found in 2006 are far more troubling, Albright said in his report. While Libya was given plans for an older and relatively unsophisticated weapon that was bulky and difficult to deliver, the newly discovered blueprints offered instructions for building a compact device, the report said. The lethality of such a bomb would be little enhanced, but its smaller size might allow for delivery by ballistic missile. “To many of these countries, it’s all about size and weight,” Albright said in an interview. “They need to be able to fit the device on the missiles they have.”
Both In addition to the obvious danger of other rogue regimes acquiring such information, it is currently unknown whether terrorists groups acquired any of the information. As the article notes, the design for a compact nuclear device in the hands of both rogue states or terrorists represents the clearing of a major hurdle allowing them to build weapons far easier to deploy than the clunky older designs.
While both rogue states and terror groups would surely like to acquire both a nuclear capability and weapons, each actor has a different set of advantages and disadvantages. States enjoy legitimacy (to varying extents) and international recognition, have sovereign territory and have a variety of reason and fear based national interests. Critically, states are also subject to deterrence through retaliation by sometims deterrence by denial (more here). Terror groups, on the other hand, have less power, resources and people than states do. Yet, terrorists are more difficult to deter by retaliation often lacking any clear target to retaliate against. In addition, some follow radical ideologies unrestrained by reason or straight up political goals.
While it wouldn’t have served the IRA’s interest to crash planes into London, it did serve al-Qaeda’s. And regarding nuclear terrorism, deterrence by denial is a far more difficult and costly option. Hence, an aggressive strategy against rogue states aims to both uncover, disrupt and neutralize threats, it also brings traditional deterrence to bear on potential collaborators with terrorists thereby deterring states not only from aiding terrorists but also motivating them to fight such networks themselves in the interest of their state’s and their own survival.
While details continue to slowly emerge, one thing remains certain, America’s breakup of Khan’s network and aggressive pursuit of rogue states and proliferaters has been an important unsung success of the Bush Administration which suffers from the typical dynamic that success means nothing happens.
On a side note, The Washington Institute has an article up discussing the strategic threat of nuclear terrorism (Hat Tip to Counterterrorism Blog).

