In 2003, Secretary of State Colin Powell warned that “no threat is more serious to aviation” than lightweight, guided, portable surface-to-air missiles known as man-portable air defense systems (MANPADS). Since then, Powell’s words have been echoed by countless journalists, analysts, and government officials, who warn that a successful missile attack on a commercial airliner could kill hundreds of people and cripple the financially volatile airline industry.
On the other side of the debate are the skeptics of the MANPADS threat and the multibillion-dollar programs proposed to address it. Included in this group are pilots associations, which view the missiles as just one of many potential threats and fear that the airlines will be stuck with the bill for expensive anti-missile systems currently being evaluated by the Department of Homeland Security (DHS). Particularly outspoken is John Meehan, executive vice president of the Airline Transport Association. During a recent interview with the Dallas Morning News, Meehan downplayed the particular threat from MANPADS and ascribed the undue attention that they have received to corporate greed. MANPADS would not be the focus of so much attention, Meehan concluded, “if it were not for the vendor that was out there trying to sell a particular technology.”
As the debate over anti-missile systems heats up, the rhetoric surrounding the MANPADS threat has become increasingly exaggerated and misleading. It also tends to miss a vital point: U.S. efforts to secure or destroy such systems overseas may be more crucial to the safety of U.S. passengers and planes than high-technology programs on U.S. territory. With modest budgets and little fanfare, small teams in the Departments of State and Defense and in the intelligence community have secured and destroyed thousands of surplus and poorly secured MANPADS, collected hundreds of loose missiles from regional black markets, and established global norms and standards on the export of MANPADS that are unprecedented in their scope and specificity. Consolidating these gains and converting them into lasting security will require a thorough, nuanced understanding of the MANPADS threat and careful allocation of scarce resources.
The MANPADS Threat
Before assessing U.S. efforts to counter the threat from MANPADS, a basic overview of the weapons themselves is in order, as is some clarification concerning their availability to terrorists, the ability of terrorists to use them effectively, and the nature and consequences of a successful attack.
MANPADS are designed for use by individuals or small teams of soldiers against helicopters and other small attack aircraft. Most are heat-seeking missiles fired from a launch tube that rests on the shoulder. They are lightweight, easy to smuggle, and highly proliferated. Since their development in the 1960s, an estimated 1 million MANPADS have been produced by more than 20 countries, which have exported them to dozens more. Thousands of these missiles have been diverted to terrorists and insurgents, who have used them to shoot down hundreds of military aircraft and at least 25 civilian aircraft, including several large turbojet planes.
In 2004 the Government Accountability Office (GAO) estimated that there are 500,000-750,000 MANPADS in existence worldwide. This number is often incorrectly presented as the number of missiles available to terrorists. A good example is a recent claim by a member of the House of Representatives that “there are 700,000 [MANPADS] on the streets right now.” Although it is not clear what the lawmaker meant by “on the streets,” it appears to imply that these missiles are either available on the black market or otherwise outside of government control. According to the State Department, however, the “overwhelming majority” of MANPADS are in “national stockpiles of varying security.” The security afforded to the missiles in some countries is so rigorous that the likelihood of theft or loss is exceedingly small. In the United States, for example, stockpile security is so tight that there is not a single confirmed case of the theft or loss of Stinger missiles from military depots. Because the Defense Department demands comparable security for the missiles it exports, the vast majority of Stinger missiles in U.S. and foreign depots are probably inaccessible to most terrorists.
Estimates of loose and insecure missiles compiled by U.S. intelligence agencies probably present a more accurate reflection of the problem. In 2004, they estimated that approximately one percent of the global inventory (5,000-7,000 missiles) is outside of state control and tens of thousands more missiles are stored in government arsenals with questionable stockpile security. Although securing tens of thousands of weapons is no small task, it is much more feasible than locating and eliminating 700,000 black market missiles.
The ability of terrorists to use MANPADS is also a subject of intense debate. Using these weapons effectively is not simply a matter of “point and shoot,” as is sometimes claimed. It is “a technical skill [that] has to be maintained,” explains Christopher Hughes, an expert with the British Ministry of Defense. “Anyone…could probably pick one up and be shown how to use it and have a lucky shot but to be guaranteed a success you must be well trained and practiced.” Indeed, there are numerous examples of attacks that probably failed because of user error, including a high-profile attempt by al Qaeda to shoot down an Israeli airliner departing from Mombassa, Kenya, in 2002. Yet, history also is replete with examples of nonstate actors mastering the use of these weapons. In the 1980s, Afghan rebels shot down 269 Soviet military aircraft, including small, fast fighter jets, with their Stinger missiles, a remarkable accomplishment that is often credited with turning the tide of the war. More recently, a “highly trained” team of Iraqi insurgents shot down a DHL cargo plane with a first-generation SA-7 missile near Baghdad International Airport. Since then, missile-wielding insurgents have shot down a C-17 Globemaster cargo plane, a C-5 Galaxy transport plane, and several helicopters.
The debate over the likely consequences of a MANPADS attack also is prone to exaggeration and oversimplification. A common assumption amongst alarmists is that a single missile will invariably result in hundreds of deaths. In one colorful example, a British journalist describes a fictitious attack near Heathrow Airport. Imagining that a terrorist has fired a missile, the author asks rhetorically, “Can anything prevent hundreds of innocent people being killed in the next few seconds?” implying that the missile will inevitably hit the plane and kill everyone on board.
Others are unduly dismissive of the threat. A 2006 position statement from the Air Line Pilots Association (ALPA), for example, understates the threat by failing to mention key details about several cases in which commercial jets were hit by MANPADS. Of the attack on the DHL cargo plane in Iraq, ALPA says only that “the aircraft was struck, but safely landed with a damaged wing.” Although factually correct, the assessment does not convey the seriousness of the damage caused by the missile or the difficulty of landing the aircraft. The missile tore a hole in the wing, ignited a fire, and knocked out the plane’s hydraulic systems, rendering most flight controls useless. During their descent into Baghdad’s airport, First Officer Steve Michielsen recalls “giv[ing] himself only a 20 [percent] chance of survival.” Four years later, Christopher Hughes observed that “people have tried to replicate this incident on simulators and as yet nobody has been able to land the aircraft.”
As illustrated above, MANPADS are neither the super weapon feared by alarmists nor the paper tiger dismissed by skeptics. The threat is much more complex and requires a carefully crafted, multifaceted response.
The U.S. Counter-MANPADS Campaign
U.S. efforts to address the terrorist threat from MANPADS date back at least to 1972, but until recently, these efforts were largely reactive, modest, and ad hoc. That started to change in the late 1990s when the United States spearheaded negotiations on the first multilateral agreement on MANPADS export controls, which was adopted in December 2000 by members of the Wassenaar Arrangement, a voluntary multilateral institution that promotes rigorous controls on the export of conventional weapons and dual-use goods. By adopting the Elements for Export Controls of MANPADS, the Wassenaar Arrangement’s 40 participating states agreed to limit exports of MANPADS to other governments and require recipient governments to, inter alia, establish adequate physical security and stockpile management practices and seek permission before retransferring imported MANPADS. Two years later, an unsuccessful attempt by al Qaeda-affiliated terrorists to shoot down an Israeli airliner as it was departing from an airport in Kenya transformed this limited, largely diplomatic initiative into a full-fledged campaign. Within weeks, the United States had launched “a systematic, end-to-end countermeasures strategy…aggressively implemented through multiple agency initiatives”
Since January 2007, most proliferation control efforts have been coordinated by the MANPADS Task Force, an interagency working group comprised of nine people from the State, Defense, and Homeland Security Departments. The task force is an outgrowth of the National Strategy for Aviation Security, a comprehensive plan for “protect[ing] the Nation and its interests from threats in the Air Domain.” Seven supporting plans were developed to implement the strategy, including an “International Aviation Threat Reduction Plan.” The MANPADS Task Force is the central coordinating body for that plan, which focuses primarily on “proliferation control and threat reduction,” i.e., strengthening export controls on MANPADS, securing and destroying surplus and poorly secured missiles, and collecting missiles from nonstate entities. Below is a brief summary of U.S. efforts in each of these areas.
Lax export controls have resulted in the transfer, both deliberate and unintentional, of dozens of MANPADS to terrorists, arms traffickers, and insurgents. In the mid-1990s, for example, failure to spot discrepancies in fraudulent end-user certificates led to the delivery of 100 Bulgarian SA-7 missiles to the Angolan group UNITA. Similarly, the widespread practice of arming proxy groups, a practice that is proscribed by the Elements and other multilateral export control agreements recently adopted by many countries, has resulted in the delivery of MANPADS to other terrorist groups in Europe, the Middle East, and Africa. In the 1970s and 1980s, Libya provided MANPADS to a variety of terrorist organizations, including the Irish Republican Army and the Popular Front for the Liberation of Palestine. Even when terrorists are not the intended recipient, MANPADS provided to nonstate actors often end up in the wrong hands. The United States discovered this the hard way when dozens of Stingers it provided to Afghan rebels were diverted to unauthorized end users, including terrorists and state sponsors of terrorism.
The most significant accomplishment regarding export controls on MANPADS is the negotiation and widespread adoption of the Expanded Elements of Export Controls for MANPADS, a more detailed and extensive version of the original Elements adopted in 2003, as well as iterations drafted by the Organization for Security and Cooperation in Europe (OSCE), the Organization of American States, and the Asia-Pacific Economic Cooperation forum. The Elements are noteworthy for several reasons, including their scope, specificity, and the broad support they have garnered from the international community. Unlike many such agreements, the controls prescribed by the Elements are specific, detailed, and rigorous. Section 2.9, for example, does not merely call for “effective measures for safe storage” but lists very specific requirements, including monthly physical inventories, 24-hour surveillance, and separate storage of missiles and launchers. More than 95 countries, including most major producers and exporters of MANPADS, have adopted one or more versions of the Elements.
Although a huge step forward by any standard, these agreements do have two significant limitations. The first is the absence of monitoring and enforcement mechanisms, which puts the onus on individual states to monitor implementation. This is difficult and time-consuming. The second is that diplomats are often reluctant to “name and shame” violators. As a result, observes the GAO, “the U.S. government has little assurance that commitments by member countries to improve their controls over MANPADS will have an impact on members’ national policies and practices” and therefore “must rely upon other means for such assurance.” Secondly, several key states are not members of the institutions that have adopted versions of the Elements and are therefore under no obligation to implement them. Included in this list are known proliferators such as Pakistan, Iran, and North Korea.
Despite these limitations, the Elements and the nascent norms that they embody are already raising the bar on export controls for MANPADS. U.S. officials report gradual but concrete progress in implementing these agreements and, equally as important, a dramatic change in the mentality toward export controls on MANPADS. “Ten years ago, convincing other countries of the importance of MANPADS controls would have been difficult,” observed one U.S. official. “Now the need to control these weapons is automatically accepted.”
In addition to its significant role in negotiating the Elements, the United States has strengthened its already rigorous end-use monitoring of exported Stinger missiles, provided more than $150 million in assistance to help countries improve their export control systems, and is exploring the possibility of “buy[ing] entire countries out of the business” of producing MANPADS.
Stockpile Security and Destruction
Vulnerable state stockpiles also pose a proliferation risk, as demonstrated repeatedly by the theft or diversion of surplus weaponry from large, poorly secured arsenals in former Warsaw Pact countries, Central America, and elsewhere. In some of these countries, stockpile security is not just poor, it is nonexistent. U.S. stockpile security assistance teams have encountered “unsecured MANPADS covered in dirt…in locations where schoolchildren play” and others that were “stored in small rooms made of wood and secured by a light wooden door with a single padlock.” In another notable case, “the military had stacked its MANPADS in the crawlspace under a barracks, figuring that if anyone went into the crawlspace, the soldiers in the barracks would hear them,” recalls one U.S. official. Programs that help foreign militaries to destroy surplus missiles and secure weapons stockpiles are therefore a critical component of U.S. counter-MANPADS efforts.
Destruction assistance is coordinated by the State Department, which receives technical support from the Defense Threat Reduction Agency (DTRA). Since 2001, the State Department has facilitated the destruction of more than 21,000 surplus, poorly secured, and illicit missiles in at least 18 countries, including 3,000 missiles in Ukraine; 1,000 in Nicaragua; 233 in Cambodia; and thousands more in Bosnia, Afghanistan, Chad, Liberia, and elsewhere. According to U.S. officials, the overwhelming majority of these MANPADS were older (first-generation) systems, and most were Soviet designed infrared seekers, the MANPADS most frequently used in terrorist attacks. Most were located in national inventories, but some were discovered in abandoned arms caches and even private residences. In Liberia, State Department officials discovered two SA-7s and two SA-14s near the home of a former government minister. According to one of the officials, they found the missiles in a shed “guarded only by a chicken with no tail feathers.”
Complementing the State Department’s destruction projects are efforts to improve the physical security and stockpile management of foreign arsenals, the centerpiece of which is DTRA’s small arms and light weapons (SALW) program. The program provides foreign militaries with on-site assessments of their physical security and stockpile management (PSSM) practices and with orientations on international best practices. During orientation seminars, experts identify specific steps that the host military can take to improve its stockpile security, such as installing intrusion detection systems, conducting regular physical inventories of its missile stocks, and limiting access to missile storage rooms to teams of at least two people. Since 2002, DTRA has conducted orientation and assessment visits in more than 30 countries, the majority of which had MANPADS in their stocks. The United States also has promoted strong stockpile security through the Elements and its sister agreements, which contain specific stockpile-security measures that exporters are expected to require their clients to implement, and the joint development of an international Best Practice Guide for stockpile security through the OSCE.
Stockpile security and destruction programs are the backbone of U.S. counter-MANPADS efforts, but they are not a panacea. Not all surplus missiles are accessible to U.S. destruction teams, because the owners view them as valuable commodities, are leery of giving U.S. officials access to their weapons, or relations between the two governments are poor. A good example is the sudden suspension of the U.S.-funded program to destroy Nicaragua’s surplus MANPADS. In 2003, President George W. Bush and Nicaraguan President Enrique Bolanos agreed to a joint program to destroy Nicaragua’s entire inventory of 2,000 SA-7 missiles. Halfway through the program, however, a combination of anti-U.S. sentiment, concern over the loss of Nicaragua’s primary although largely obsolete air defense assets, and discontent over the lack of compensation for the missiles brought the program to a grinding halt. As of August 2007, the program was still stalled, although a recent offer by Nicaraguan President Daniel Ortega to destroy additional MANPADS in exchange for helicopters and medical supplies could lead to a resumption of the program. Similarly, the reach of U.S. stockpile security programs is limited to those countries willing to allow U.S. experts into their depots. Even in these cases, no physical security or management procedures, no matter how good, are completely insurmountable. For these reasons, stockpile security and destruction assistance programs are most effective when they are integrated into a broader, multifaceted counter-MANPADS strategy.
Because of the secrecy that surrounds weapons collection programs, a full accounting of these efforts is nearly impossible. Of the programs reportedly established over the past five years, the most is known about the MANPADS Weapon Buyback Program in Iraq. The program was launched in 2003 and had a budget of $1.5 million, $457,225 of which had been disbursed as of June 2005. Initially at least, cash rewards were small. According to a U.S. military press release, soldiers manning collection points in Baghdad paid just $500 apiece for complete systems (missile and launcher) and $250 for launchers alone, although a more recent source mentions much larger payments: $1,500 for a complete SA-7 and $10,000 for a complete SA-14 or SA-16. The number of missiles collected is classified, but public accounts suggest that the program netted at least several hundred missiles, including more than 200 from a single individual.
Regular reports of MANPADS attacks on coalition aircraft and seizures of missiles from insurgent caches suggest that the program was only partially successful. Also significant are unconfirmed reports that “cash-rich al Qaeda in Iraq cells have purchased MANPADS at twice the ‘buyback’ price being offered by the coalition and have distributed these to insurgent cells.” Although larger rewards would have been prudent, there is no guarantee that more cash would have netted significantly more missiles. Weapons collection programs rarely recover more than a fraction of loose MANPADS. In the early 1990s, large CIA payouts for loose Stinger missiles in Afghanistan sparked bidding wars that drove up black market prices to $100,000 or more per missile. Despite these large payouts, 600 of the estimated 2,000 Stingers provided to the mujahideen remained at large as of 1996.
The United States is also pursuing a variety of other activities aimed at improving security at airports and defending airliners against launched missiles. Particularly noteworthy are programs to develop anti-missile systems for airliners, which have already consumed hundreds of millions in taxpayer dollars and dominated media coverage of U.S. counter-MANPADS efforts. The DHS launched the program in 2003 to determine the “viability, economic costs, and effectiveness” of adapting military anti-missile systems for use on civilian aircraft. Three years later, the DHS announced the establishment of a parallel program to explore “emerging countermeasure technologies,” including unmanned aerial vehicles equipped with laser jammers and ground-based systems that use microwaves and high-energy lasers to deflect or destroy missiles.
Since 2003, Congress has appropriated $270 million for these activities. Should the government decide to mandate the use of these systems at U.S. airports or by U.S. airlines, the cost to taxpayers and/or the airline industry would likely run in the billions. Yet, these systems would be at best a partial solution even if they live up to expectations. Plane-mounted laser jammers are ineffective against certain types of MANPADS, provide no protection to Americans flying on foreign airliners, and could be overwhelmed by several missiles fired simultaneously. The two ground-based systems under review by the DHS are reportedly effective against all types of MANPADS but provide no protection to U.S. airliners flying overseas. If history is any indicator, it is at foreign airports that U.S. airliners are most vulnerable. The cost of ground-based anti-missile systems also is daunting despite attempts to sell them as cost-effective alternatives to plane-mounted systems. Raytheon boasts that its Vigilant Eagle system would be “30 times more cost effective over a 20-year life cycle” than plane-mounted systems, but the $2 billion cost estimate only covers installation and maintenance at the 35 largest commercial service airports. Why an attack on Raleigh-Durham International Airport (#36), which handled 217,099 flights in 2006, would be less likely or devastating than an attack at Honolulu International Airport (#35 with 217,874 flights), is not explained in the fact sheet.
For these reasons, policymakers should carefully study the limitations and opportunity costs associated with anti-missile systems before signing off on their widespread deployment. Anti-missile systems would provide another layer of protection, but unless the shortcomings identified above are overcome, the protection they provide is not commensurate with their collective multibillion-dollar price tags. Selective installation on certain aircraft deemed particularly vulnerable to MANPADS may be prudent but only if doing so does not divert resources from other, more cost-effective counter-MANPADS initiatives.
Assessing U.S. Counter-MANPADS Efforts
Over the last five years, the United States has done much to combat the terrorist threat from MANPADS. U.S. policies and programs have facilitated the destruction of a significant percentage of the world’s vulnerable missiles, improved stockpile security in depots containing thousands more missiles, established international standards on export controls, and removed hundreds of missiles from the black market. According to one U.S. official, these efforts have already had some effect on the illicit trade in MANPADS. There is “specific evidence that, in certain regions, our efforts have made it more costly and difficult to illicitly acquire MANPADS.”
Converting these gains into real security, however, requires additional progress on all fronts. Illicit MANPADS are still readily available in many parts of the world, as evidenced by recent reports from the Middle East, Africa, South America, and eastern Europe. Because even a handful of functioning missiles in the hands of trained terrorists pose an acute threat to civilian aviation, complacency will inevitably lead to an unraveling of the notable gains achieved thus far. Below are several suggestions for further reducing the number of missiles available to terrorists and their desirability as tools of terrorism.
First, donor states should continue to expand their stockpile security and destruction assistance programs. Thousands of missiles worldwide remain vulnerable to varying degrees to theft and diversion. Given the cost effectiveness and accomplishments to date of stockpile security and destruction programs, there is little reason not to expand these programs until they fully meet existing needs.
Second, the United States and like-minded governments should also press for universal adherence to the Elements, particularly its prohibition on MANPADS transfers to nonstate actors. Several rogue regimes continue to transfer missiles to terrorists and insurgents, sometimes in large quantities. Last year, the United Nations accused Iran, Syria, and Eritrea of providing dozens of MANPADS to Islamic insurgents in Somalia, and Western intelligence agencies reported additional Iranian shipments to Lebanon and Iraq. The international community and particularly the main trading partners of the offending regimes must take decisive action against this threat, including the imposition of increasingly rigorous economic sanctions if these countries refuse to halt MANPADS transfers to nonstate actors. Failure to do so will weaken fledgling norms on the storage and export of these weapons and leave unchecked a ready source of missiles for terrorists and insurgents worldwide.
Third, it is essential to prevent another MANPADS proliferation disaster like the looting of Iraqi arsenals. After the fall of Saddam Hussein’s regime in 2003, as many as 4,000 missiles were pilfered from Iraqi arms stockpiles, leading to an estimated threefold increase in the number of black market missiles worldwide. In response to this looting, the GAO recommended that the U.S. military “incorporate conventional munitions storage site security as a strategic planning factor into all levels of planning policy and guidance.” This is an important step, but such changes will be of little use if there are not enough boots on the ground to implement them. Senior military and civilian leaders must ensure that future military campaigns are adequately staffed and resourced to locate and secure weapons depots and expeditiously destroy surplus stockpiles.
Finally, states that produce MANPADS should develop and install launch control devices. No stockpile security and export controls, regardless of their rigor, can prevent every attempted theft or diversion. Therefore, technology must be developed that limits the utility and lifespan of lost, stolen, and diverted missiles. One device flagged for this role by Robert Sherman, a former director of special projects for the Arms Control and Disarmament Agency, is the controllable enabler. Although still a drawing board concept, the enabler illustrates the potential effect that launch-control devices could have on the availability of and demand for illicit missiles. As explained by Sherman, controllable enablers are chip-level features that require the input of an electronic code before a missile will activate. The missile could be “enabled” for any period of time, but after the code expires, it must be entered again or the missile will not function. Widespread use of such devices would shorten the effective lifespan of lost, stolen, or diverted missiles from decades to as little as a few days or hours. Enablers also could reduce demand for MANPADS amongst terrorists, who may be hesitant to invest thousands of dollars in a weapon that might stop working immediately before a carefully planned attack.
As with other counter-MANPADS strategies, launch control features would not be a panacea. Rogue states such as Iran and corrupt individuals with access to enabling codes presumably would continue to distribute unprotected or inappropriately enabled missiles to terrorists. When combined with existing efforts, however, enablers would add another critical layer of protection from wayward missiles, particularly those that are inadvertently released from government inventories.
By any standard, U.S. counter-MANPADS efforts have been remarkably successful, especially given the short time since their founding. With more time and resources, the United States and like-minded members of the international community could strike a decisive blow against the illicit trade and use of MANPADS but only if policymakers pursue the most effective counter-MANPADS strategies and use scarce resources wisely.
3. Christopher Bolkcom and Bartholomew Elias, “Homeland Security: Protecting Airliners From Terrorist Missiles,” CRS Report for Congress, RL31741, February 16, 2006; Bureau of Political-Military Affairs, Department of State, “The MANPADS Menace: Combating the Threat to Global Aviation From Man-Portable Air Defense Systems,” September 20, 2005 (fact sheet).
6. U.S. official, interview with author, Washington, D.C., July 2007; Government Accountability Office (GAO), “Further Improvements Needed in U.S. Efforts to Counter Threats From Man-Portable Air Defense Systems,” GAO-04-519, May 2004.
7. Chris Hughes, “MANPADS: What They Do and How They Do It,” Presentation at “Effective Strategies to Mitigate the Threat Posed by the Use of Man-Portable Air Defense Systems (MANPADS) by Nonstate Actors,” Washington, D.C., March 8, 2007 (presentation before the Organization of American States).
16. U.S. official, interview with author, Washington, D.C., July 2007. Because of the sensitive nature of activities aimed at eliminating terrorist MANPADS holdings, collecting missiles from other nonstate actors, and reining in proliferation by “bad actor states,” public information on these programs is scant or nonexistent. Therefore, coverage of these activities is limited to a few recent examples of weapons collection programs.
17. UN Security Council, “Report of the Monitoring Group on Somalia,” S/2007/436, July 2007. In this context, the term “export controls” refers both to the mechanisms used by governments to prevent the unauthorized transfer of weapons and the criteria used to determine who is eligible to receive authorized shipments.
32. See Department of Homeland Security, “DHS Awards $7.4 Million in Combined Contracts to Three Firms to Support Emerging Counter-MANPADS Technologies,” October 20, 2006 (press release); “High Altitude Endurance Unmanned Aerial System (HAE UAS)-Based Counter-MANPADS Technology Assessment,” HSARPA BAA07-04, March 27, 2007.
37. From July to November 2006, UN investigators documented the delivery of no fewer than six sanctions-busting arms shipments containing more than 120 MANPADS to Islamic rebels in Somalia; the Salvadoran government revealed a plot to assassinate President Tony Saca involving an SA-7 missile that authorities found close to a landing zone for the president’s helicopter; and Russian police seized four SA-7 missiles from a criminal group attempting to sell them to undercover officers.