Homeland Security:

Progress Has Been Made to Address the Vulnerabilities Exposed by 9/11, but Continued Federal Action Is Needed to Further Mitigate Security Risks

GAO-07-375: Published: Jan 24, 2007. Publicly Released: Jan 24, 2007.

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Five years after the terrorist attacks of September 11, 2001, GAO is taking stock of key efforts by the President, Congress, federal agencies, and the 9/11 Commission to strengthen or enhance critical layers of defense in aviation and border security that were directly exploited by the 19 terrorist hijackers. Specifically, the report discusses how: (1) commercial aviation security has been enhanced; (2) visa-related policies and programs have evolved to help screen out potential terrorists; (3) federal border security initiatives have evolved to reduce the likelihood of terrorists entering the country through legal checkpoints; and (4) the Department of Homeland Security (DHS) and other agencies are addressing several major post-9/11 strategic challenges. The report reflects conclusions and recommendations from a body of work issued before and after 9/11 by GAO, the Inspectors General of DHS, State, and Justice, the 9/11 Commission, and others. It is not a comprehensive assessment of all federal initiatives taken or planned in response to 9/11. GAO is not making any new recommendations at this time since over 75 prior recommendations on aviation security, the Visa Waiver Program, and U.S. Visitor and Immigrant Status Indicator Technology (US-VISIT), among others, are in the process of being implemented. Continued monitoring by GAO will determine whether further recommendations are warranted.

While the nation cannot expect to eliminate all risks of terrorist attack upon commercial aviation, agencies have made progress since 9/11 to reduce aviation-related vulnerabilities and enhance the layers of defense directly exploited by the terrorist hijackers. In general, these efforts have resulted in better airline passenger screening procedures designed to identify and prevent known or suspected terrorists, weapons, and explosives from being allowed onto aircraft. Nevertheless, the nation's commercial aviation system remains a highly visible target for terrorism, as evidenced by recent alleged efforts to bring liquid explosives aboard aircraft. DHS and others need to follow through on outstanding congressional requirements and recommendations by GAO and others to enhance security and coordination of passengers and checked baggage, and improve screening procedures for domestic flights, among other needed improvements. GAO's work indicates that the government has strengthened the nonimmigrant visa process as an antiterrorism tool. New measures added rigor to the process by expanding the name-check system used to screen applicants, requiring in-person interviews for nearly all applicants, and revamping consular officials' training to focus on counterterrorism. Nevertheless, the immigrant visa process may pose potential security risks and we are reviewing this issue. To enhance security and screening at legal checkpoints (air, land, and sea ports) at the nation's borders, agencies are using technology to verify foreign travelers' identities and detect fraudulent travel documents such as passports. However, DHS needs to better manage risks posed by the Visa Waiver Program, whereby travelers from 27 countries need not obtain visas for U.S. travel. For example, GAO recommended that DHS require visa-waiver countries to provide information on lost or stolen passports that terrorists could use to gain entry. We also recommended that DHS provide more information to Congress on how it plans to fully implement US-VISIT--a system for tracking the entry, exit, and length of stay of foreign travelers. While much attention has been focused on mitigating the specific risks of 9/11, other critical assets ranging from passenger rail stations to power plants are also at risk of terrorist attack. Deciding how to address these risks--setting priorities, making trade-offs, allocating resources, and assessing social and economic costs--is essential. Thus, it remains vitally important for DHS to continue to develop and implement a risk-based framework to help target where and how the nation's resources should be invested to strengthen security. The government also faces strategic challenges that potentially affect oversight and execution of new and ongoing homeland security initiatives, and GAO has deemed three challenges in particular--information sharing, risk management, and transforming DHS as a department--as areas needing urgent attention. DHS and the Department of State reviewed a draft of this report and both agencies generally agreed with the information. Both agencies provided technical comments that were incorporated as appropriate.

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