The term weapons of mass destruction (WMDs) has been applied to many types of weapons that cause extensive death and catastrophic destruction. The use of WMDs in foreign policy specifically refers to weapons of nuclear, chemical, and biological warfare—often collectively referred to as NBC weapons. The definition of WMDs under US federal law includes explosive and incendiary bombs, rockets, or grenades capable of inflicting mass casualties.
Possessing, conspiring to use, and attempting to use WMDs are serious criminal offenses in the United States, frequently resulting in terrorism charges. The development and possession of WMDs are regulated and restricted by international treaties. The United States, along with other countries, categorizes radiological weapons such as "dirty bombs"—devices intended to disperse radioactivity without an atomic explosion—as weapons of mass disruption because of their potential to cause widespread panic and contamination.
Early Use of Nuclear, Biological, and Chemical Weapons
WMDs have been deployed in wartime. During World War I (1914–1918), poison gases such as chlorine, phosgene, and mustard gas were dispersed in huge quantities by the German, British, French, and US armies, causing more than one million casualties and nearly one hundred thousand deaths. The worldwide condemnation of these atrocities led to the negotiation of the Geneva Protocol in 1925, a treaty prohibiting the use of asphyxiating or poisonous gases and biological agents in warfare.
During World War II (1939–1945), the Japanese used biological and chemical weapons in China, and the German Nazi regime employed chemical agents to put millions of people to death in its concentration camps throughout Europe. The Allies used coordinated aerial firebombing in their attacks on Dresden, Hamburg, and Tokyo. Hundreds of Allied forces airplanes dropped thousands of tons of conventional high explosives, killing tens of thousands of people in each city. During the final days of the war in the Pacific, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki, incinerating large urban areas with a single nuclear weapon, killing tens of thousands immediately and over several weeks from radiation.
State and non-state actors have used chemical weapons against civilians. In an attack known as the Halabja Massacre on March 16, 1988, Iraqi jets under the command of Saddam Hussein spread poison gas over a town captured by Kurdish rebels during the Iran–Iraq War. The chemical attack included mustard gas and nerve agents. Estimates put the number of victims at five thousand. Many others died after the attack due to disease and contamination. Syrian government forces under the Bashar al-Assad regime stockpiled chemical weapons and repeatedly attacked civilian populations with poisonous gas between 2012 and 2018, including a sarin attack that killed hundreds of civilians in Damascus in 2013. Non-state actors have also obtained and used chemical weapons. Islamic State (ISIS) militants in Iraq fired mortars containing sulfur mustard gas against Kurdish military fighters in 2016.
A large-scale biological or germ warfare attack has never taken place. Terrorism experts believe that this is due to the difficulties of dispersal and a variety of factors that could potentially mitigate the effects of such an attack, such as wind and weather patterns, antidotes, and other public health responses. According to chemical and technological experts, the impact of WMDs depends on a wide range of variables such as the means of delivery; the purity and density of the agent; climate factors that would affect the agent's diffusion, dilution, or evaporation; and precautionary measures taken by the target population.
WMDs and Foreign Policy
Efforts to prevent the use of WMDs have historically taken the form of international treaties, beginning with the 1925 Geneva Protocol. The first resolution adopted by the United Nations (UN) General Assembly on January 24, 1946, called for the establishment of a commission to make recommendations for "the elimination from national armaments of atomic weapons and of all other major weapons adaptable to mass destruction." These diplomatic endeavors resulted in agreements to outlaw biological and chemical weapons and to restrict lawful possession of nuclear arsenals to a select group of countries. In the decades following World War II, political and military leaders gradually came to conceive of WMDs as part of a single class of armaments, distinct from conventional arms due to the magnitude of their destructive capabilities.
Considering all WMDs, nuclear weapons represent the greatest threat to international security. The UN Non-Proliferation of Nuclear Weapons Treaty (NPT) entered into force in 1970. The United States ratified the treaty that same year. The purpose of the NPT was to prevent the worldwide development of nuclear weapons by restricting national development and working toward complete nuclear disarmament while allowing countries to develop nuclear energy for nonmilitary applications. As of March 2020, 191 nations were party to the NPT.
The United States ratified the UN Biological Weapons Convention (BWC) when it entered into force in 1975. This treaty bans the production, acquisition, and stockpiling of biological weapons but does not contain any provision for inspections. The number of states party to the BWC totaled 183 in March 2020.
The UN Chemical Weapons Convention (CWC), adopted in 1992, prohibits chemical weapons and calls for disarmament. The CWC created an inspection regime, administered by the Organization for the Prohibition of Chemical Weapons (OPCW) and based in The Hague, Netherlands. As of March 2020, there were 193 states parties to the CWC, including the United States, which ratified the convention in 1997.
Pursuing Nuclear Disarmament
The core of the NPT, the main international treaty governing nuclear arms, is an agreement between the five nuclear-weapon states—the United States, United Kingdom, France, Soviet Union (now Russian Federation), and China—and non-nuclear-weapon states. Non-nuclear weapon states agreed to forswear development or acquisition of nuclear weapons but are permitted to develop nuclear technology for energy generation. Nuclear weapon states agreed in Article VI of the treaty to engage in disarmament negotiations. Several nations, including Israel, Pakistan, India, and North Korea, have chosen to not be parties to the NPT and have developed and stockpiled nuclear warheads. The 2020 NPT Review Conference marks the fiftieth anniversary of the treaty. The Security Council issued a press release in February 2020 underscoring a continued commitment to international nuclear disarmament.
The Cold War (1945–1991) led to a nuclear arms race, mainly between the United States and the Soviet Union. The two countries negotiated several bilateral nuclear nonproliferation agreements after the Cold War to pacify tensions and commit to a reduction in nuclear arms. The first Strategic Arms Reduction Treaty (START I) between the United States and the Russian Federation entered into force in December 1994. START I limited the number of nuclear warheads and delivery vehicles, including missiles, providing a framework for further reductions that were completed by December 2001.
New START entered into force in 2011, further limiting nuclear warheads and launchers and calling for both the United States and the Russian Federation to be subject to on-site inspections. The requirements were met by the February 2018 deadline. According to the Arms Control Association, more than 90 percent of the world's nuclear arsenal belongs to these two countries, which held 12,675 nuclear warheads between them in July 2019. New START will expire in February 2021, unless it is renewed by both sides for a period of five years. In August 2019 the United States formally withdrew from the 1988 Intermediate-Range Nuclear Forces Treaty (INF) after accusing the Russian Federation of violating the pact. Critics worry that withdrawal from this Cold War–era treaty will lead to a renewed nuclear arms race.
Attempts by several governments and dictators to obtain WMDs have caused international alarm during the twenty-first century. In 2003 the United States claimed to possess credible intelligence that Iraqi dictator Saddam Hussein was developing nuclear WMDs, posing an imminent danger to the international community. No evidence of WMDs was ever located in the aftermath of the invasion.
Iran's attempt to enrich nuclear materials to develop weapons has posed a challenge to the international community. Iran agreed to the Joint Comprehensive Plan of Action (JCPOA) in 2015, which compelled the nation to refrain from developing nuclear weapons and commit to restricting itself to peaceful enrichment for energy programs. US president Donald Trump announced in May 2018 that the United States would no longer comply with the agreement and instead again imposed sanctions on Iran aimed at hampering its economy.
North Korea's development of nuclear weapons and delivery systems has been of concern to the international community for decades. The nation announced intentions to withdraw from the NPT in 2003. North Korea possessed an estimated thirty nuclear warheads in 2019 and continued to test ballistic missiles, threatening South Korea, Japan, and the United States. Despite several meetings with leader Kim Jong-un starting in June 2018, President Trump failed to effectively convince North Korea to halt the country's nuclear warhead and delivery system development program. The regime launched several short-range projectiles in March 2020.
WMDs and US Domestic Policy
Investigations and intelligence collection on WMDs in the United States are tasks of the WMD Directorate (WMDD), which was established in 2006. WMDD falls under the National Security Branch of the Federal Bureau of Investigation (FBI). The federal agency works with partners, including the Joint Terrorism Task Force, local and state law enforcement officials, universities, and industries to address the threat of potential WMD attacks against the country domestically and abroad.
Federal charges have been brought against US citizens for possessing weapons classified as WMDs. A woman from Queens, New York, was sentenced to fifteen years imprisonment in January 2020 for her role in planning to build and providing information on making and using WMDs. The categorization of certain weapons as WMDs has also been controversial. For example, the Supreme Court of North Carolina decided in February 2020 that flash-bang grenades should be categorized as WMDs under federal law because they meet the official definition of explosive or incendiary bombs and grenades. Critics argue that these devices are not capable of causing catastrophic death and destruction. Flash-bang grenades are frequently used by law enforcement to disperse hostile crowds.