MANPADS are portable short-range surface-to-air missile systems designed for use by one or two soldiers to attack fixed-wing aircraft and helicopters during wartime. Basic components include the launch tube and missile, gripstock (launcher or firing mechanism), and thermal battery. See figure 1 for an illustration of MANPADS components. Due to growing concern in the late 1990s over the worldwide proliferation of MANPADS to non-state actors, the United States led an effort to promote improved export control policies for MANPADS, primarily in the Wassenaar Arrangement. In December 2000, the 33 Wassenaar Arrangement participating states adopted U.S.-proposed guidelines for establishing a set of MANPADS export controls. While multilateral export control regimes are a key policy instrument in the overall U.S. strategy to combat the proliferation of weapons of mass destruction and conventional weapons, they have limitations. The multilateral export control regimes are voluntary, nonbinding arrangements among like-minded supplier countries. While countries make no legally binding commitments in joining them, participating countries undertake a political commitment to abide by the goals and principles of the regime. The regimes operate on the basis of consensus of all members and decisions on how to implement and interpret regime decisions are left to the national discretion of each member. None of the regimes identify specific countries as targets. Collectively the regimes strive to stop, slow, or increase the cost and risk of detection efforts by countries’ of concern to acquire sensitive technologies and capabilities, including MANPADS. The United States began selling its current MANPADS, the Stinger missile system, to U.S. allies and U.S.-approved nations in 1982. Because the Stinger missile system is among the most advanced of all MANPADS, the United States has placed enhanced controls and requirements on its sale and use. (See fig. 2 for a picture of the U.S. Stinger missile system.) Under security assistance procedures, DOD provides defense articles, services, and training to foreign governments and international organizations that have been approved by the State Department and determined by the President as supporting U.S. national security and foreign policy objectives, according to DOD. In comments on a draft of this report, DOD said that each proposed transfer of Stinger missiles is thoroughly vetted by many different organizations and offices, thus providing DOD a high level of confidence that the missiles under security assistance programs do not pose a terrorist threat. The Stinger missile system is one of only a few weapons systems that are subject to “enhanced end-use monitoring” by DOD. If a Stinger missile system sale is approved through the Foreign Military Sales process, State and DOD sign and extend a letter of offer and acceptance (LOA) to the customer nation. The LOA serves as a contract agreement between the United States and the customer nation and requires the customer nation to allow DOD to conduct annual inspections to ensure the Stinger systems are being used and stored as required under the terms of the sale. Countries that purchase Stinger missile systems from the United States are legally bound to cooperate with these inspections or risk damaging future military sales and cooperative relations with the United States. Notwithstanding U.S. controls over its Stinger missile systems, the concern over a potential MANPADS attack against commercial aircraft has grown in recent years. According to the U.S. government, terrorists are aware of the severe economic consequences that a MANPADS attack could wreak on the U.S. economy. In November 2002, terrorists used a MANPADS to attack, but miss, a commercial airliner in Mombasa, Kenya—the first such attack outside an area of conflict. Following this attack, according to DOD officials, the National Security Council created an interagency task force to pursue several options to reduce the risk of MANPADS attack, including the feasibility of transferring counter-MANPADS technology from U.S. military aircraft to U.S. commercial aircraft. In response to the conference report accompanying the Emergency Wartime Supplemental Appropriations Act, 2003, DHS began to review a variety of technical options for counter-MANPADS systems with a goal of selecting a system within 2 years for use on the U.S. commercial aircraft fleet. DHS is now working with private contractors to develop a counter-MANPADS system. MANPADS pose a threat to commercial aircraft for several reasons. First, MANPADS are widely available. The U.S. government estimates that thousands of MANPADS worldwide are outside government controls. Thousands more under government controls may be vulnerable to theft and possible transfer to terrorist groups through illicit arms markets because they are not subject to stringent national export standards nor do they have adequate physical security. Second, MANPADS characteristics make them attractive to terrorists. Finally, MANPADS have been successfully used to attack and bring down aircraft. Since the 1950s, 20 countries have developed or produced at least 30 different types of MANPADS, with a total production of more than a million missiles. The majority of MANPADS are either located within military arsenals; have been expended in live-fire exercises, wars, insurgencies, or other conflicts; or have been destroyed, according to State Department officials. Estimates of the global inventory of MANPADS range from 500,000 to 750,000 weapons, with approximately 1 percent outside the control of national governments, according to intelligence sources. In addition, according to the State Department, the numbers of MANPADS in the global inventory are difficult to estimate because destruction of MANPADS systems is not always publicized and the systems’ effective lifetimes depend on how they are stored and maintained. Table 1 shows the 20 countries that have developed or produced MANPADS since the 1950s. During the cold war, the United States, the Soviet Union, and their allies provided MANPADS to several client states in surrogate cold war conflicts. For example, the U.S. government transferred hundreds of Stinger missiles in the mid-1980s to Afghan rebels that were fighting Soviet forces in Afghanistan. U.S. intelligence officials stated that a number of these weapons may have fallen into the hands of terrorist groups. The State Department estimates that at least nine nonstate groups, including al Qaeda, have obtained some type of MANPADS. Some MANPADS produced during the cold war were surplus to countries’ defense needs in the 1990s. These MANPADS became widely available on the black and gray arms markets where terrorists could acquire them. The black arms market consists primarily of weapons that have been stolen from government or private holdings, seized by combatant forces, supplied by state sponsors to subnational groups, or produced illegally. Black market transfers usually involve a small number of arms that do not move through official licensing channels and are difficult to detect. Gray arms sales can be large and involve sales of advanced weapons systems. Such sales generally move through official government licensing channels and rely on false documentation or other deceptive means to disguise the buyer, supplier, type of weaponry, or another component of the transaction. There are known black markets in Afghanistan, the Balkans, Iraq, Lebanon, Somalia, Southeast Asia, and Yemen, according to the State Department. Gray arms shipments of MANPADS to Africa have been delivered mostly to countries that divert the weapons to subnational groups. The new security challenges in Iraq have added to the global stockpile of MANPADS available on the black and gray markets. According to intelligence sources, thousands of MANPADS may have been provided to Iraqi security forces or were stolen during hostilities in Iraq immediately following the collapse of the Saddam Hussein regime in 2003. Therefore, the number of MANPADS outside national controls may have doubled. The U.S. government is also concerned that thousands of MANPADS under the control of some foreign governments may be vulnerable to theft and possible transfer to terrorist groups through the black and gray markets. Some countries lack stringent national export standards, which increases the likelihood that MANPADS will fall into the hands of terrorists, according to the State Department. For example, China, Egypt, former Yugoslavia, North Korea, and Pakistan have produced MANPADS but are not Wassenaar Arrangement members. In 2000, Wassenaar Arrangement members adopted the first multilateral guidelines for controlling the export of MANPADS and strengthened these guidelines in 2003. In addition, the U.S. government is concerned about the physical security and inventory controls of MANPADS within certain countries’ arsenals, where MANPADS are vulnerable to theft and possible transfer to terrorist groups. For example, as of September 2003, the U.S. government had identified at least 17 countries whose security over their MANPADS stockpiles raised concerns. These countries included Bosnia and Herzegovina, Liberia, Cambodia, Nicaragua, and Serbia. Total stockpiles of MANPADS in these 17 countries are believed to number in the tens of thousands, according to the State Department. MANPADS are attractive to terrorists for acquisition and use against commercial aircraft because they are lethal, easy to use, transport, and conceal, and they are relatively inexpensive. MANPADS are designed to be lethal. Frequently called heat-seeking missiles, most MANPADS models employ sensors that search for and home in on the target’s infrared signature, often the engine. Newer MANPADS can recognize specific aircraft characteristics and reject simple countermeasures or distractions, according to a defense manufacturer. MANPADS are effective up to approximately 15,000 feet in altitude and 3 miles in range. Thus, while aircraft generally are safe from MANPADS when flying at cruising altitude (30,000 feet), they are most vulnerable during take off and landing. MANPADS systems are relatively easy to use but do require training. An individual rests the weapon on his or her shoulder, looks through a sight, and pulls a trigger.