United States Chemical Overview

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The United States is a party to the Chemical Weapons Convention (CWC), does not have an active offensive chemical warfare (CW) program, and is destroying its chemical weapons stocks, some of which remain from World War I.

The United States developed a robust CW program beginning near the end of World War I. The program continued until the early 1990s when President George H.W. Bush and Soviet President Mikhail Gorbachev signed a bilateral accord to end the production of new chemical weapons and significantly reduce CW stockpiles. Subsequently, the United States ratified the CWC on 24 April 1997, which obligated it to dismantle its CW program and destroy all CW stocks. As of December 2013 the United States has destroyed 90% of its Category I agents and all of its Category II and III agents, and is scheduled to destroy the remaining stocks by 2023. ¹ The United States has made extensive efforts to support global CW nonproliferation by providing political and technical support for the dismantlement of the Syrian, Libyan, and Albanian CW programs.

1918 to 1949: Early Efforts

The United States commenced researching chemical weapons in 1917 near the end of World War I. Initially, the U.S. Bureau of Mines managed this program because of its experience with mine gases. However, on 28 June 1918 the United States founded the Chemical Warfare Service (CWS), a dedicated agency for CW efforts. ² The Edgewood Arsenal in Maryland was central to CWS efforts. Several facilities were built there for the development and manufacture of CW agents, and for munitions filling. ³ Work initially focused on developing phosgene, chlorine, chloropicrin mustard gas, hydrogen cyanide, bromobenzyl cyanide, diphenylchloroarsine (a vomiting agent), and lewisite (first discovered by an American scientist in 1918). ⁴ In addition to CW agent development, the CWS was also responsible for CW defense efforts, including the acquisition of large numbers of gas masks for humans and horses. The Edgewood Arsenal’s staff would eventually peak at over 7,000 military officers and enlisted personnel, producing a larger quantity of CW agents than England and France combined. ⁵

Research and development activities tapered off after World War I; however, the CWS still maintained CW specialists and facilities. Some CWS resources were redirected toward civil chemical applications, including the development of new chemicals to prevent barnacles from attaching to ships and insecticide to protect crops from boll weevils.

In the mid to late 1930s, interest in and support for the CW program began to increase as the possibility for another major war in Europe loomed. The U.S. Congress initially allocated funds to the CWS to develop a basic offensive chemical weapons stockpile; funding to the CWS was increased after Germany invaded Poland in 1939, and continually thereafter prior to U.S. entry into World War II. ⁶ This funding was primarily used to build new facilities for research and development, as well as production plants managed by private industry. ⁷

During World War II, the need to prepare for possible enemy chemical attacks drove the United States’ CW policy. ⁸ The CWS increased its efforts to acquire protective equipment and train soldiers in its proper use. In addition to defensive measures, the United States produced large quantities of offensive CW agents; during World War II this included, in total, 43.8 tons of unpurified sulfur mustard; 4,500 tons of purified sulfur mustard; 20,000 tons of lewisite; and 100 tons of nitrogen mustard. ⁹ The United Kingdom also provided the United States with chemical weapons, including 6,500 500-pound bombs filled with phosgene. ¹⁰ The U.S. Army’s primary chemical weapon delivery system during World War II was the 4.2 inch mortar, which could fire shells filled with either CW agents or high explosives. ¹¹ The United States military also produced a large number of 105 millimeter (mm) and 155 mm artillery shells filled with mustard gas. ¹² By the end of World War II the U.S. Army had established 32 chemical mortar brigades, 11 chemical mortar companies, and additional support units. ¹³

Shortly after World War II ended, interest in chemical weapons waned. In 1947, Congress cut two-thirds of the Chemical Corps’ (the Chemical Warfare Service was renamed in 1946) budget and closed the Dugway Proving Ground, a major development and open-air testing site. ¹⁴ In addition, between 1946 and 1948 the United States disposed of most of its 20,000-ton stock of lewisite by dumping it into the oceans. ¹⁵

1950 to 1969: CW During the Cold War

Increasing tensions between the United States and the USSR, as well as the outbreak of the Korean War in June 1950 led the U.S. military to develop a renewed interest in chemical weapons. Five days after the start of the war, the Ad Hoc Committee on Chemical, Biological and Radiological Warfare submitted its report (also known as the Stevenson Report) advocating a strong focus on chemical weapons to counter Russian efforts, and an end to the retaliation-only policy that had been the norm. ¹⁶ Almost all of the Stevenson’s Reports’ recommendations were accepted, although the retaliation-only policy remained. As a result of those recommendations, over the next year-and-a-half the Chemical Corp’s budget tripled, the number of researchers was increased from 2,100 to 3,700, and the Dugway Proving Grounds were reopened for testing chemical weapons munitions. ¹⁷

During the 1950s production focused primarily on the nerve agent sarin, as it has more military utility and is easier to manufacture relative to other nerve agents. ¹⁸ The precursor chemicals needed to synthesize sarin are methylphosphonic dichloride (referred to as dichlor), sodium fluoride, and isopropyl alcohol. The U.S. manufacturing process for sarin involved two separate activities out of concern about possible sabotage or attack: first, the precursor chemical dichlor was produced at facilities in Muscle Shoals, Alabama; and second, sarin was synthesized at the Rocky Mountain Arsenal near Denver, Colorado. ¹⁹ Despite some initial difficulties and delays in the production of dichlor, the Rocky Mountain Arsenal soon was producing thousands of tons of sarin per year. ²⁰ This continued until 1957 when the military determined it had a sufficient supply of sarin and both facilities were shut down. The Chemical Corps also produced new delivery systems including 105mm and 155mm artillery shells, as well as the M35 cluster bomb (designed to be filled with sarin). U.S. researchers also developed 2-PAM (pralidoxime chloride) for defensive purposes, a highly effective nerve agent antidote when combined with atropine.

In 1961, the United States began Project 112 to examine the strategic impact of chemical and biological weapons. ²¹ Project 112 found that both chemical and biological weapons should be seen as a part of a broader strategy of “gradual deterrence” in which chemical or biological attacks could serve as intermediary steps to deter the Soviet Union without resorting to nuclear weapons. ²² As a result of this finding, the budget of the Chemical Corps nearly tripled between 1961 and 1964. ²³

Project 112’s work coincided with efforts to develop new chemical weapons agents and delivery systems. In the late 1950s, the military had become interested in the new V-series of nerve agents (sarin belongs to the G-series), and particularly in VX due to its greater lethality and persistence (sarin is non-persistent). Following extensive research and pilot testing, production of VX began in 1961 at the Newport Chemical Depot near Terre Haute, Indiana, which produced between 4,000 and 5,000 tons of VX by 1967. ²⁴ In addition to VX agent, the military produced new delivery systems for both sarin and VX including the M55 rocket, the Honest John rocket, VX-filled landmines, and 750-pound aerial bombs for sarin. However, production of these munitions was insufficient, and as a result production of VX was ended in 1968 due to a lack of delivery systems with which to pair it. ²⁵

While chemical weapons production was ramping up, the United States military also conducted extensive tests. Following Project 112’s recommendations, the Deseret Test Center at Fort Douglas, Utah was created to oversee extensive testing of biological and chemical weapons over land and using barges in far off areas of the Pacific Ocean. ²⁶ At least fifty trials were conducted between December 1962 and 1970 (though it is important to note that these trials involved both biological and chemical weapons tests). ²⁷ (Project 112’s sea trials, referred to as Shipboard Hazard and Defense (SHAD), generated controversy in later years, when former Navy personnel argued that the tests had had a strong negative impact on their health.) ²⁸

During the Vietnam War, the CW program came under extensive criticism by both Congress and the public after several incidents. In March 1968 over 6,000 sheep in Utah were killed after a cloud of VX gas released over the Dugway Proving Grounds drifted off the testing range. ²⁹ This event was heavily publicized by a documentary on the U.S. chemical and biological weapons program on NBC’s “First Tuesday” TV show, leading to major public and congressional backlash. ³⁰ There was also extensive concern over revelations that the United States military had been dumping old chemical weapons from the World War II-era at sea under Operation Cut Holes and Sink ‘Em (CHASE). ³¹

1969 to 1985: A 17-Year Moratorium

U.S. President Richard Nixon’s Secretary of Defense, Melvin R. Laird, launched a review of biological and chemical weapons policies and programs on April 30, 1969 in response to public and congressional concerns. However, the CW part of the review quickly became moot because in August 1969 Congress unilaterally initiated a moratorium on the production of new chemical weapons. ³² After having read the findings of Laird’s review, President Nixon issued his “Statement on Chemical and Biological Defense Policies and Programs” on 25 November 1969. The statement reaffirmed the United States’ commitment to no first use of lethal chemical weapons, extended that commitment to non-lethal chemical weapons, and committed the president to submitting the 1925 Geneva Protocol to the Senate for ratification. ³³

In the late 1960s, Chemical Corp scientists achieved a major technological advance when they developed so-called binary CW agents. Briefly, a binary weapon is one that carries two relatively innocuous precursors in separate compartments until it is used. Once the weapon has been launched, the wall between the compartments is breached and the two precursors are mixed. The resulting chemical reaction produces a toxic nerve agent, either VX or sarin. In 1979, the Department of Defense sought approval from Congress to construct a pilot plant for new binary CW agents. ³⁴ Although Congress approved funding for the construction of the pilot plant at Pine Bluff Arsenal, the request touched off a broader public debate about the value of binary chemical weapons that continued until the mid-1980s. ³⁵ The military argued that it was necessary to replace the aging CW stockpile that had been neglected since the 1960s moratorium began with new binary chemical agents, and also claimed that they were safer to handle than unitary agents. ³⁶ The Reagan administration in the 1980s agreed with these claims, but also asserted the importance of having effective chemical weapons in order to counter the threat posed by the Soviet Union. According to the U.S. Army, when faced with a possible or real CW attack, Soviet soldiers would be forced to don Personal Protective Equipment (PPE), which would degrade their fighting effectiveness by as much as fifty percent. ³⁷ However, opponents argued that the weapons would create political problems with NATO allies since some of them would have to store the new munitions for rapid deployment in case of a Soviet attack. Other opponents questioned the value of CW in general because of the weapons’ supposed limited military efficacy and potential for generating civilian casualties. ³⁸

1985 to 1990: Reversing the Moratorium

In 1985 President Reagan officially reversed the moratorium on chemical weapons development and Congress approved his request to begin production of binary VX and sarin. ³⁹ At the same time, due to mounting concerns that the aging stockpile posed potential safety hazards, many of the United States’ older chemical weapons were ordered destroyed. ⁴⁰ In fact, the Department of Defense Authorization Act for 1984 mandated that for the production of each new 155mm artillery shell or aerial bomb filled with a binary chemical weapons agent, a unitary weapon must be destroyed. ⁴¹ In order to alleviate allied opposition to the new weapons, production of new agents was conditioned on approval by a NATO committee. ⁴²

In addition to new binary weapons agents, the Reagan administration approved the development and production of new delivery systems. Thus the military successfully produced M-687 binary artillery rounds. However, the major focus for munitions development was the 500lb Bigeye Bomb that had been in development since the 1960s. ⁴³ The Bigeye posed significant technical challenges; a 1989 memo from the Government Accountability Office stated that the Bigeye had serious design flaws. ⁴⁴ In addition, attempts to develop sarin and VX binary warheads for M55 rockets used by the U.S. Multiple-Launch Rocket System (MLRS) were unsuccessful. ⁴⁵

1990 to 1993: Bilateral U.S.-USSR CW Reductions

The U.S. position on CW was reversed again on 1 June 1990 when presidents George H. W. Bush and Mikhael Gorbachev signed a bilateral accord that enjoined the USSR and United States to significantly reduce their chemical weapons stockpiles over the next decade. ⁴⁶ Specifically, both leaders agreed to reduce their declared stockpiles to only 5,000 tons by 2002, with an interim goal of fifty percent destruction of the declared stockpiles by 1999. ⁴⁷ Furthermore, both states would end production of new chemical weapons and allow on-site inspections for verification purposes. In 1992, the U.S. Army Chemical Material Destruction Agency (renamed Chemical Materials Agency in 2003 following several other name changes) was established to oversee all destruction activities, including making certain that they were safely conducted. ⁴⁸

1993 to the Present: CWC Ratification and CW Destruction

On 13 January 1993 the United States signed the CWC. However, the U.S. Senate delayed ratifying the treaty due to concerns about the treaty’s verifiability and domestic political infighting in the Senate. Much of the delay stemmed from Senator Jesse Helms (R-NC), Chairman of the Senate Foreign Relations Committee, who sought to use CWC ratification as leverage against the Clinton Administration by holding the treaty in committee to gain support for his goal of reorganizing the U.S. foreign affairs bureaucracy. ⁴⁹ In addition to viewing the ratification process as a political tool, Helms was concerned about the treaty’s ability to carry out its stated goals, fearing that compliance to the treaty could neither be verified nor enforced, leading to a false sense of security among treaty members. ⁵⁰

Following a compromise deal brokered by Senator John Kerry (D-MA), the treaty was allowed out of committee on 30 April 1996 for an eventual vote on the Senate floor. In exchange, Helms received Democratic support for developing a bipartisan bill to restructure the foreign affairs bureaucracy. ⁵¹ Originally, the vote was scheduled to occur before 14 September 1996; however, it fell victim to the divisive political atmosphere prior to the November 1996 presidential election and was thus again delayed.

After President Clinton’s re-election, the administration focused on building public and Congressional support for ratification, including by hosting a rally on 4 April 1997 on the lawn of the White House, with prominent political and military figures from both parties in attendance. ⁵² Eventually, the vote was held on 24 April 1997, at which time the amendments creating conditions for U.S. ratification were defeated, and the CWC was successfully ratified. ⁵³

After the United States successfully ratified the CWC, Congress still needed to pass implementing legislation to put the terms of the treaty into practice, and used that opportunity to unilaterally include three exceptions to CWC provisions. ⁵⁴ First, the United States reserved the right to refuse an on-site inspection by the Organization for the Prohibition of Chemical Weapons (OPCW). ⁵⁵ Second, chemical samples could not be removed from the U.S. for analysis at overseas labs. Third, the number of facilities subject to declaration and inspection would be greatly limited. Consistent with the CWC, the United States drew up plans for destroying its remaining stockpile of chemical weapons and developed a list of chemical facilities to declare to the OPCW as part of its required initial declaration.

Capabilities

The United States had produced a wide variety of different chemical weapons agents since the CW program’s beginnings in World War I. Early efforts focused on mustard gas, phosgene, and chlorine, among others, based on recommendations from France and Britain during World War I. During World War II, the United States produced hundreds of thousands of tons of new chemical agents with a focus on blister agents, including lewisite, sulfur mustard, and nitrogen mustard. During the 1950s and 1960s focus shifted towards developing new nerve agents and producing 4,000 to 5,000 tons of VX and thousands of tons of sarin. Production of VX took place at the Newport Chemical Depot outside of Terre Haute, Indiana. Bulk chemical agents were stored at Tooele Army Base in Utah. ⁵⁶ The Edgewood Arsenal has served as the primary facility for agent development and production. In addition to the agents themselves, the United States constructed a wide variety of delivery vehicles including mortars of several sizes, 100lb bombs, artillery shells, spray tanks, chemical mines, bomblets, and missiles for their delivery.

As of December 2012 declarations to the OPCW, the United States still possessed 3,134 tons of chemical weapons agents, consisting of mustard gas, sarin, and VX. These agents are scheduled to be destroyed by 2023 after construction of the necessary destruction facilities.

Following ratification of the CWC, the United States was scheduled to destroy its offensive CW stockpile by 2007; however, delays pushed back the deadline until 2023. ⁵⁷ Nevertheless, by December 2013, 90% of the Category I agents and all of the Category II and III agents in the U.S. stockpile had been destroyed. The remaining chemical weapons agent stockpiles slated for destruction are located at the Chemical Depot in Pueblo, Colorado and the Blue Grass Army Depot in Richmond, Kentucky, where destruction plants were recently constructed. ⁵⁸ The Colorado facility contains 2,611 tons of mustard gas in filled 105mm and 155mm projectiles and 4.2 inch mortar cartridges. ⁵⁹ The Blue Grass Army Depot contains 523 tons of the nerve agents VX and sarin, as well as mustard gas in filled munitions. ⁶⁰ The Chemical Depot in Pueblo is in its final testing phase and will begin destroying mustard agents by 2017. ⁶¹ The Blue Grass Army Depot will start a multi-year testing phase by destroying simulated nerve agents. ⁶² The other facilities that once produced chemical weapons agents and delivery systems have since been decommissioned. ⁶³

The United States has also played a key role in furthering global norms against chemical weapons. In 2004 the United States was extensively involved with the destruction of a large previously unknown stock of chemical weapons in Albania. The Defense Threat Reduction Agency (DTRA) of the Department of Defense funded a German company to design and equip a small, portable chemical weapons disposable facility that could be transported through the country’s mountainous terrain. ⁶⁴ In September 2013, negotiations between the United States and Russia led to an agreed upon framework to dismantle Syria’s CW program. The United Nations Security Council endorsed this framework, and the OPCW adopted a decision on destruction of Syria’s chemical weapons based on this framework on 27 September 2013. ⁶⁵ To carry out the destruction, DTRA developed a Field Deployable Hydrolysis System (FDHS) that was deployed on the U.S. cargo ship Cape Ray. ⁶⁶ The FDHS has completed the neutralization of 600 tons of sulfur mustard and DF, a sarin precursor. ⁶⁷