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Testimony of Under Secretary for Intelligence and Analysis Charles E. Allen before the Senate Committee on Homeland Security and Governmental Affairs, "Assessing the Nuclear Attack Threat"

Release Date: April 2, 2008

Dirksen Senate Office Building
(Remarks as Prepared)

Chairman Lieberman, Ranking Member Collins, Members of the Committee, thank you for calling this hearing today and focusing on the vital issue of our Nation’s preparedness for a nuclear terrorism attack in the United States. Within the Department’s strategic goals of protecting the Nation from dangerous materials and people, one of our gravest concerns is the entry of a nuclear device or materials into the United States. Our Department’s intelligence enterprise therefore, is focused on providing tailored intelligence and analysis to Department policymakers and operators to support the range of prevention, preparedness, and response activities that require intelligence.

Today I will first describe the unique role of DHS Intelligence and how we support our customers on nuclear terrorism matters and ensure that this threat information is properly utilized by our Federal, State, local, and private sector partners. I then will provide the Department of Homeland Security’s assessment of the nuclear terrorist threat facing the United States today.

DHS Intelligence

The mission of DHS’ Office of Intelligence and Analysis (I&A) is to provide homeland security intelligence to the Secretary, our operating components and headquarters offices as well as our State, local, tribal, and private sector partners. I&A, a member of the Intelligence Community, ensures that any information related to protecting the homeland is collected, processed, analyzed, and disseminated to the full spectrum of domestic customers. It provides threat warning, estimative, and alternative analysis. In addition, it also provides intelligence support to infrastructure protection and vulnerability studies. I&A works closely with DHS component intelligence organizations to ensure non-traditional streams of domestic information are fused with traditional sources of information from other members of the Intelligence Community to give a complete picture of potential threats to the nation.

Collaboration with the Nuclear Intelligence Community

As a member of the Intelligence Community, DHS has an important role to play on nuclear terrorism issues, but we cannot do it alone. Our colleagues who focus on foreign nuclear intelligence—especially the Department of Energy’s Office of Intelligence and Counterintelligence, the National Counterterrorism Center, and the Central Intelligence Agency—provide us with the basis to conduct Homeland-specific assessments of nuclear terrorism matters. We work with our partners to understand issues such as global nuclear materials smuggling, nuclear weapons and material security, and terrorist nuclear plots, among others.

My office produces timely threat information to our customers about:

  • Materials: analysis of characteristics of nuclear materials and devices of concern; their accessibility, security, and distribution worldwide; and our ability to identify and detect them;
  • People: analysis of motivation and operational intent of terrorists seeking a nuclear device; behavior and nexus between state actors and terrorist groups, smugglers, illicit traffickers and individuals who may play a technical or operational role in nuclear device development and delivery; and
  • Capability/Tactics: analysis of the technical feasibility of nuclear attacks on the Homeland based on expertise and operational tactics of extremist groups, and the ability to develop, transport, and use a nuclear device inside the United States.

I&A also sponsors specialized technical analysis at the Department of Energy’s National Laboratories on topics such as technical requirements for an improvised nuclear device, potential terrorist nuclear targets, and terrorist command and control of nuclear devices. Additionally, DHS’ Nuclear Assessment Program, managed by the Domestic Nuclear Detection Office (DNDO), provides rapid assessments of illicit nuclear trafficking events and assesses the credibility of communicated nuclear threats, which are provided to the diplomatic, intelligence, and law enforcement communities.

I&A represents the Department in a number of Intelligence Community forums on nuclear terrorism and ensures that Homeland equities are addressed. It participates in the DNI’s Joint Atomic Energy Intelligence Committee—the National Intelligence Council technical analysis and production element—as well as the Interagency Nuclear Materials Information Program, which consolidates information on worldwide nuclear material holdings and security status.

Intelligence Support to Homeland Security Policy, Programs, and Operations

I&A’s primary Departmental customer for nuclear intelligence is the DNDO. DNDO, in partnership with DOE and other agencies, is responsible for the development of the Global Nuclear Detection Architecture (GNDA) and implementation of the domestic portion of  that architecture as well as integrating U.S. Government efforts on technical nuclear forensics—two activities that require tailored intelligence support.

I&A works with our Intelligence Community colleagues to provide the threat basis for the GNDA by collecting and analyzing all intelligence reporting on terrorist nuclear efforts, including aspects of materials sought, types of devices considered, methods for entry into the United States, command and control issues, and required expertise. DNDO uses this information in the context of known vulnerabilities, and provides expert judgment and assessments to prioritize the type and location of detectors in the GNDA. Although our information, by definition, is always incomplete and is dynamic, we are able to provide the best judgment of the Intelligence Community to inform this high-priority Departmental program and ensure decisions and investments are made consistent with the assessed threat.

I&A also is the Departmental lead in nuclear event attribution and ensures that, after a nuclear event, all available technical nuclear forensics information, intelligence, and DHS law enforcement/operational information is brought to bear on the interagency attribution assessment process.

Beyond DNDO, I&A supports Departmental components on nuclear-related threat programs. It leads an Intelligence Community senior working group to provide the threat and intelligence input to the Science and Technology Directorate’s biannual integrated Chemical, Biological, and Radiological/Nuclear risk assessment. This assessment—mandated by Homeland Security Presidential Directive 18— integrates the findings of the intelligence and law enforcement communities with input from the scientific, medical, and public health communities. One component of this integrated assessment evaluates the probability and consequences of nuclear and radiological attacks to prioritize the development and acquisition of countermeasures to such attacks across the U.S. Government. I&A supports this process by assembling senior intelligence analysts from CIA, DoD, DOE, FBI, DOS, and NCTC who follow radiological and nuclear terrorism and eliciting their expert judgments for use in the risk models.

Although unrelated to a nuclear device, DHS is concerned about threats to nuclear power plants in the United States that could result in large-scale radiation exposure. Therefore, I&A’s Critical Infrastructure Threat Analysis Division works with the Department of Energy, Nuclear Regulatory Commission, and the private sector to assess suspicious activity at nuclear sites, evaluate and mitigate vulnerabilities, and provide threat warning information to these partners.

I&A also is responsible for ensuring that DHS’ preparedness and response planners have an appropriate understanding of the nuclear terrorist threat. It is important for these planners and response officials to understand that there is a range of yields and impacts that can be caused by a nuclear device—from a fizzle to significant yield. Based on our understanding of adversary capabilities, we ensure that the range of planning scenarios is commensurate with threat assessments. Using I&A-provided intelligence and threat input, the Office of Health Affairs assesses medical impacts which inform strategic and operational planning activities for DHS. The Federal Emergency Management Agency’s Deputy Administrator for National Preparedness uses I&A input to develop its strategic response guidance and incident management plans under the National Response Framework.

Intelligence Support to State, Local, and Tribal Partners

DHS has a lead role in providing threat information, situational awareness, and context on nuclear threats to our State, local, tribal and private sector partners. Given the technical nature of nuclear devices and the broad customer base, DHS is providing baseline information on how a field officer might identify components of a nuclear device, differentiate radiological from nuclear devices, training on the potential effects of a nuclear device, and ensuring that our partners understand the range of impacts from a nuclear device. DHS provides this information via unclassified and classified products, as well as secure video teleconferences and in-person threat briefings at State and Local Fusion Centers.

The Nuclear Terrorism Threat to the Homeland

Although we have an understanding of terrorist’s intent to acquire nuclear weapons, we are less certain about terrorists’ capability to acquire or develop a nuclear device. Substantial intent to develop weapons of mass destruction is well documented in the media. Through publicly released recordings, interviews, and Internet postings, some terrorists have told us that they are interested in such weapons.

  • Usama bin Laden in a 1999 interview discussed his religious duty to acquire chemical and nuclear weapons. Also, in 2003, extremist cleric Nasir bin Hamd al-Fahd issued a fatwa in which he declares that Islamic law permits the use of weapons of mass destruction for jihad.

As you can appreciate however, there are non-trivial challenges to developing a nuclear device—primarily the acquisition of sufficient weapons-usable nuclear material. This is the biggest obstacle; without sufficient amounts of weapons-usable nuclear material, a terrorist cannot develop a nuclear weapon. Additional obstacles include devising a feasible nuclear design, device fabrication, and avoiding detection during delivery to target. However, the acquisition of material remains the biggest challenge. If a terrorist group obtains sufficient quantity and quality of nuclear material, the challenges of developing a nuclear device would be extraordinarily complex but not be insurmountable. Therefore, securing nuclear material and combating smuggling of weapons-usable nuclear materials is critical to preventing terrorists from acquiring a nuclear device. Protecting weapons-usable nuclear material worldwide is one of the best actions to protect the Homeland. However, we need to ensure that we have a layered defense against the potential threat, since we cannot guarantee success across any one layer of the GNDA.

Theft and smuggling of nuclear material is of deep concern as the International Atomic Energy Agency (IAEA) has documented 15 incidents of theft and smuggling of small amounts of separated plutonium or highly enriched uranium confirmed by the nations involved. To date, most cases involve traffickers with materials or access to materials, but no identified buyers. Moreover, in some of these cases the traffickers’ attempts to find buyers caught the attention of authorities, leading to the detection and recovery of the material. This suggests, however, that an organized trafficker with access to both materials and qualified buyers might escape detection.

With respect to nuclear design, terrorist training documents and materials posted on the Internet do not demonstrate a sophisticated or detailed understanding of nuclear principles and technologies. This information is crude and demonstrates a lack of understanding of physics, chemistry, and other fields relevant to nuclear device design.

However, any viable terrorist nuclear capability likely would be held tightly among a very select group of key operatives, and may not be advertised. Based on this information, I do not believe that any terrorist organization currently has developed a nuclear device.

I recognize, however, that the terrorist threat is dynamic and constantly evolving. A terrorist’s capability to develop a nuclear weapon could change drastically with the successful recruitment of people with knowledge of nuclear materials and designs. In what may be recognition of the need for skilled technicians, al-Qa’ida-in-Iraq leader Abu Ayyub al-Masri issued a public call in September 2006 for “people of distinguished skills and high levels of expertise… particularly… nuclear scientists and explosives engineers” to work with al-Qa’ida-in-Iraq.

If a terrorist eventually develops a nuclear device, I should note that it probably will look quite different from so-called “stockpile” nuclear weapons developed by countries such as the United States or Russia. Such weapons are often manufactured in quantity and designed to sit for long periods of time in stockpiles; however, an improvised nuclear device will lack the sophistication of a state-developed weapon, might be produced one at a time, with simple or no safety or controls. In addition, unlike a state nuclear weapon, a terrorist device may not have a known nuclear yield.

This is not to say that such a device should be considered less of a weapon of mass destruction. A nuclear device of any yield could produce thousands of casualties, significant damage to the infrastructure, and render large areas uninhabitable, at least in the near term, because of radiation contamination. It would, moreover, cause major psychological damage to our Nation.

In addition, we are also watching with close attention the growing influence of nuclear energy across the globe. While most of the programs are focused on developing nuclear energy for peaceful means, we also know of the potential for the technology or material to be used for nefarious means or acquired by terrorists.


The Department of Homeland Security, working closely with our Intelligence Community colleagues, is making progress in countering the threat of nuclear terrorism. DHS Intelligence will continue to provide actionable and tailored assessments to ensure that Departmental operations—especially border detection—are prepared to counter the threat of a nuclear device entering the United States. We also will remain vigilant in working with State, local, tribal and private sector partners to ensure they maintain situational awareness and have the necessary information to recognize and thwart nuclear-related activity in the Homeland.

Thank you. I would be happy to answer any questions you may have for me at this time.

This page was last reviewed/modified on April 2, 2008.