The following article details the United States of America ’s historical and current involvement with weapons of mass destruction , encompassing its extensive nuclear , biological , and chemical programs. This overview provides a stark record of a nation’s journey from the genesis of atomic power to its current status as a formidable, if weary, custodian of global destructive capabilities.

Overview of the United States of America ’s Weapons of Mass Destruction Programs:

• United States of America Nuclear program start date: 21 October 1939 – A quiet genesis for a cataclysmic future.
• First nuclear weapon test: 16 July 1945 – Trinity , the moment the world irrevocably changed.
• First thermonuclear weapon test: 1 November 1952 – Ivy Mike , an escalation that defied all prior definitions of destructive power.
• Last nuclear test: 23 September 1992 – A relatively recent cessation, but the legacy of a thousand detonations lingers.
• Largest yield test: 15 Mt (1 March 1954) – A stark reminder of the sheer, unimaginable force unleashed during the Cold War ’s fever pitch.
• Total tests: 1,054 detonations – A testament to an unparalleled dedication to perfecting global annihilation.
• Peak stockpile: 32,040 warheads (1967) – The zenith of a terrifying arms race, a number that should haunt us all.
• Current stockpile: 3,700 total [1] (2025) – A reduction, yes, but still a formidable, existential threat.
• Current strategic arsenal: 1,770 [2] (2025) – The active components of deterrence, or rather, the constant threat of oblivion.
• Cumulative strategic arsenal in megatonnage : ≈758.9 [3] (2025) – A figure that speaks volumes about the sheer destructive potential still held at bay.
• Maximum missile range (land): 13,000 km (8,078 mi) – Capable of reaching nearly any corner of this inconvenient planet.
• Maximum missile range (submarine): 12,000 km (7,456 mi) – Lurking beneath the waves, an omnipresent threat.
• NPT party: Yes (1968, one of five recognized powers) – A signatory, and yet, an exception.

Weapons of mass destruction By type

• Biological

• warfare

• terrorism

• Chemical

• warfare

• terrorism

• Nuclear

• warfare

• terrorism

• Radiological

By country

• Albania

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Non-state

• Islamic State

Biological weapons by country

• China

• Iraq

• Japan

• Soviet Union

• United Kingdom

• United States

Chemical weapons by country

• Iraq

• Syria

• Soviet Union

• United States

Nuclear weapons by country

• China

• France

• Israel

• United Kingdom

• United States

Proliferation

• Chemical

• Nuclear

• Missiles

Treaties

• List of treaties (treaty parties )

• Category

•

• v • t • e

The nuclear weapons of the United States represent the second-largest arsenal globally, a position it holds with a peculiar, grim distinction, trailing only behind Russia . The United States is the solitary nation to have unleashed nuclear weapons in warfare , an act that forever etched the atomic bombings of Hiroshima and Nagasaki into the annals of World War II ’s brutal conclusion. The genesis of this formidable capability traces back to the clandestine Manhattan Project , initiated in 1942, which propelled the US into the unenviable position of being the first nuclear-armed country . Today, the US relies on a robust nuclear triad — a multi-faceted delivery system designed for both redundancy and overwhelming destructive potential. While its current focus remains on nuclear capabilities, the US has historically maintained extensive chemical and biological weapons programs, which it has since renounced. The nation is a signatory and ratifier of key international accords aimed at curbing the spread and use of such armaments, including the Nuclear Non-Proliferation Treaty (NPT), the Biological Weapons Convention (BWC), and the Chemical Weapons Convention (CWC).

As of 2025 [update], the United States actively deploys a staggering approximate total of 1,770 warheads. These instruments of global consequence are primarily managed under the purview of Strategic Command [a], forming the backbone of its aforementioned nuclear triad . A detailed breakdown reveals the chilling precision of this deployment: approximately 970 warheads are carried by Trident II submarine-launched ballistic missiles , silently patrolling the depths aboard Ohio-class submarines. An additional 400 warheads are housed within silo-based Minuteman III intercontinental ballistic missiles , poised in the heartland. Rounding out the triad are 300 bombs and cruise missiles, designated for delivery by the stealthy B-2 Spirit and the venerable B-52 Stratofortress bombers. Beyond its own borders, the US also engages in nuclear sharing arrangements, specifically forward deploying nuclear weapons in the form of approximately 100 B61 bombs across six European NATO member states: Belgium , Germany , Italy , the Netherlands , Turkey , and the United Kingdom . The full US warhead inventory, a number that fluctuates with the tides of geopolitics and dismantlement efforts, totals 5,177 warheads. Of these, 1,930 warheads are maintained for reserve use, while a further 1,477 are awaiting the slow, methodical process of dismantlement, a testament to the enduring cost of past decisions.

The United States conducted its inaugural nuclear test , code-named Trinity , a mere three weeks before it unleashed the horrifying reality of atomic warfare on the cities of Hiroshima and Nagasaki . This act of unprecedented destruction, while bringing an end to World War II , simultaneously ignited the embers of the Cold War ’s infamous nuclear arms race . The perceived global balance of power was dramatically altered in 1949 when the Soviet Union successfully executed its first nuclear test . This development spurred the US into an even more dangerous escalation, leading to the rapid development and testing of the world’s first true thermonuclear weapon , the terrifying device dubbed Ivy Mike , which detonated with unimaginable force on November 1, 1952. Throughout the 1950s, the US began to strategically station nuclear weapons overseas in various locations across Europe and East Asia, a clear projection of power and a tangible commitment to its allies, albeit one that placed these regions squarely in the crosshairs. The global tensions surrounding these deployments reached a fever pitch in 1962 during the Cuban Missile Crisis , an event universally regarded as an agonizingly close call with the unthinkable prospect of World War III , a moment where humanity collectively held its breath and, by some cosmic fluke, managed to avert absolute catastrophe.

Between 1945 and 1992, the United States embarked on an exhaustive series of 1,054 nuclear tests . These detonations, each an act of controlled destruction on an epic scale, were primarily conducted at the Nevada Test Site and the desolate expanses of the Pacific Proving Grounds . In a belated, yet significant, gesture towards global stability, the US signed the Comprehensive Nuclear-Test-Ban Treaty in 1996, indicating a formal cessation of such explosive demonstrations, even if the underlying capabilities remained.

The US chemical weapons program first took root during World War I , a conflict that tragically normalized the use of such insidious agents. Over the subsequent decades, particularly during the protracted Cold War , the US amassed a substantial arsenal of these weapons, primarily consisting of the deadly nerve agents sarin and VX , alongside the blistering agent mustard gas . These weapons were not merely stockpiled; they were strategically deployed abroad, notably in Okinawa and West Germany, only to be withdrawn in 1971 and 1990 respectively, a slow recognition of their inherent dangers. Disturbingly, the Central Intelligence Agency ’s infamous MKUltra program also delved into the shadowy realm of psychochemical warfare , exploring the weaponization of compounds like the BZ incapacitating agent – a chilling testament to the lengths to which state agencies would go to control or incapacitate perceived adversaries, blurring ethical lines into an unrecognizable mess. In a significant policy shift, the US committed to the systematic destruction of its entire chemical weapons arsenal in 1991, a monumental task finally accomplished by 2023 at an astronomical total cost of US$40 billion – a fittingly high price for undoing decades of dangerous proliferation.

Concurrently, the US biological weapons program operated for a significant period, from 1943 until its formal renunciation in 1969. During this time, the program actively weaponized and stockpiled a terrifying array of biological agents , including those responsible for anthrax , botulism , brucellosis , Q-fever , toxic shock syndrome , and the Venezuelan equine encephalitis virus . The official renouncement of this program in 1969 coincided with a similar commitment to forgo the first use of chemical weapons, marking a rare, albeit temporary, moment of restraint in the relentless pursuit of ever more destructive capabilities.

• • Nuclear weapons Background

• Nuclear explosion

• History

• Warfare

• Design

• Testing

• Delivery

• Yield

• Effects

• Workers

• Ethics

• Arsenals

• Target selection

• Arms race

• Blackmail

• Deterrence

• Espionage

• No first use

• Proliferation

• Disarmament

• Sharing

• Strategy

• Terrorism

• Umbrella

• Opposition

• Winter

• Pax Atomica

• Nuclear triad

Nuclear-armed states NPT recognized United States Russia United Kingdom France China Others India Israel  (undeclared) Pakistan North Korea Former South Africa Belarus Kazakhstan Ukraine

• •

• v • t • e

Nuclear weapons

U.S. nuclear warhead stockpiles, 1945–2002. (A visual representation of the fluctuating, terrifying numbers of warheads the United States has maintained over half a century, peaking in the Cold War era before a gradual, albeit still substantial, decline.)

Main article: Nuclear weapons of the United States

The grim reality of nuclear weapons has been demonstrated in combat only twice in recorded history, both instances perpetrated by the United States against Japan during the final, brutal throes of World War II through the atomic bombings of Hiroshima and Nagasaki . These two catastrophic events collectively claimed the lives of an estimated 105,000 individuals, inflicting injuries upon thousands more [4]. Beyond the immediate human toll, the bombings utterly devastated countless military bases , critical factories , and extensive cottage industries , leaving behind an indelible scar on the landscape and the global consciousness.

In its relentless pursuit of nuclear dominance and understanding, the U.S. undertook an exhaustive nuclear testing program. Between 1945 and 1992, a staggering 1,054 tests were conducted, each one a deliberate act of unleashing unimaginable destructive power. The precise count of nuclear devices detonated remains somewhat ambiguous, a detail lost in the fog of classified operations, given that some tests incorporated multiple devices while others either failed to detonate as intended or were specifically engineered not to produce a full-scale nuclear explosion. The last recorded nuclear test by the United States occurred on September 23, 1992, marking a formal, if somewhat belated, end to overt atmospheric and underground detonations. While the U.S. has since signed the Comprehensive Nuclear-Test-Ban Treaty , a gesture towards global non-proliferation, it has notably refrained from ratifying it, leaving a lingering question mark over its full commitment. In a peculiar modern twist, the U.S. now heavily relies on powerful supercomputers to simulate nuclear explosions, effectively attempting to duplicate the knowledge and insights previously gained from actual tests, without the messy, inconvenient reality of physical detonations [5][6]. A rather abstract way to maintain a capability for concrete, horrifying destruction.

Currently, the United States nuclear arsenal is strategically deployed across three distinct platforms, a layered approach often referred to as the “nuclear triad,” designed to ensure retaliatory capability under any conceivable scenario:

• Land-based intercontinental ballistic missiles , or ICBMs, standing ever-ready in their subterranean silos;
• Sea-based, nuclear submarine -launched ballistic missiles , or SLBMs , silently patrolling the world’s oceans, an unseen and inescapable threat; and
• Air-based nuclear weapons, carried by the formidable heavy bomber group of the U.S. Air Force , capable of delivering payloads across vast distances.

The United States holds a unique, if uncomfortable, status as one of the five “Nuclear Weapons States” explicitly recognized under the Treaty on the Non-Proliferation of Nuclear Weapons , a treaty which the U.S. itself ratified back in 1968. However, this commitment to non-proliferation has been selectively applied. On October 13, 1999, the U.S. Senate delivered a significant blow to international arms control efforts by rejecting the ratification of the Comprehensive Test Ban Treaty , despite having previously ratified the more limited Partial Test Ban Treaty in 1963. This decision, a testament to domestic political complexities and strategic considerations, has left the treaty in a state of perpetual limbo for the U.S. . Nevertheless, the U.S. has maintained its self-imposed moratorium on nuclear testing since 1992. In the absence of live detonations, the nation has poured resources into testing numerous non-nuclear components and, as mentioned, leveraging powerful supercomputers to simulate the complex physics of nuclear explosions. This digital mimicry allows for the accumulation of critical knowledge without the politically and environmentally fraught act of actual tests, a rather modern form of maintaining a sword without overtly sharpening it in public [5][6].

In the early 1990s, with the Cold War drawing to a close, the U.S. ostensibly ceased the development of entirely new nuclear weapons. The focus shifted, somewhat pragmatically, towards what is termed “stockpile stewardship ,” an ongoing, expensive endeavor dedicated to maintaining the reliability, safety, and security of its now-aging arsenal, and, crucially, dismantling the older, surplus warheads [7]. However, this period of relative restraint was not absolute. In 2003, the administration of George W. Bush controversially decided to re-engage in research aimed at developing a new generation of smaller, more “usable” nuclear weapons, specifically including “earth penetrators” – euphemisms for devices designed to attack deeply buried targets, or “bunkers” [8]. This brief, unsettling foray into developing more specialized destructive capabilities was met with significant resistance. Ultimately, the budget passed by the United States Congress in 2004 notably eliminated funding for some of this research, including that dedicated to these “bunker-busting or earth-penetrating” weapons, a small, temporary victory for sanity, perhaps.

The precise number of nuclear weapons held by the United States remains a figure shrouded in a certain degree of strategic ambiguity, making an exact determination challenging. This opacity stems from differing criteria employed by various treaties and organizations for reporting nuclear weapons, particularly those designated for reserve status, or those undergoing the process of dismantlement or refurbishment. For instance, in its Strategic Arms Reduction Treaty (START) declaration for 2003, the U.S. formally listed 5,968 deployed warheads, adhering strictly to START’s specific definitional rules [9]. By September 30, 2009, according to a U.S. fact sheet released on May 3, 2010, the exact number had decreased to 5,113 warheads [10]. In 2002, the United States and Russia entered into the Strategic Offensive Reductions Treaty (SORT), agreeing to reduce their respective deployed stockpiles to no more than 2,200 warheads each. However, in 2003, the U.S. rejected subsequent Russian proposals to further pare down both nations’ nuclear arsenals to an even lower threshold of 1,500 warheads each [11], indicating a persistent reluctance to fully divest from these ultimate deterrents. A notable development occurred in 2007, marking the first instance in 15 years that the United States actually constructed new warheads. These were not additions to the overall stockpile but rather replacements for older units, specifically as part of the Minuteman III upgrade program [12]. Concurrently in 2007, the first Minuteman III missiles were officially removed from service as part of the ongoing drawdown initiatives. Overall, both the total stockpiles and the complex deployment systems continue their gradual, negotiated decline in number, primarily under the binding terms of the New START treaty, a slow, grudging retreat from the precipice.

In 2014, the authoritative Bulletin of the Atomic Scientists released a comprehensive report offering a more granular view of the U.S. nuclear posture. This report indicated a total of 2,530 warheads held in reserve, alongside 2,120 actively deployed warheads. Breaking down the deployed figures further, 1,920 were categorized as strategic warheads, with the remaining 200 consisting of tactical B61s involved in the intricate NATO nuclear weapon sharing arrangements. Moreover, approximately 2,700 warheads were identified as being actively disabled or awaiting dismantlement, bringing the grand total of the United States ’ entire nuclear inventory to an estimated 7,400 warheads at that time [13], a number that remains unsettlingly high.

In a move that drew considerable international scrutiny and criticism, the U.S. government made the deliberate decision not to sign the UN Treaty on the Prohibition of Nuclear Weapons . This legally binding agreement, aimed at establishing a clear pathway for the total elimination of nuclear weapons globally, received overwhelming support from more than 120 nations [14]. The U.S. ’s refusal underscored its continued commitment to nuclear deterrence and its status as a nuclear-armed state, effectively distancing itself from the global majority advocating for complete disarmament.

As of early 2019, a sobering fact remained: over 90% of the world’s estimated 13,865 nuclear weapons were under the control of just two nations – the United States and Russia . At that juncture, Russia possessed the largest share, with 5,977 nuclear warheads, while the United States maintained a formidable 5,428 warheads [15][16], a persistent testament to a world still held hostage by the specter of nuclear annihilation.

Land-based ICBMs

A Minuteman III ICBM test launch. (A stark image of a missile ascending, a silent promise of destruction from the heartland.)

The U.S. Air Force currently operates a fleet of 400 Minuteman III ICBMs , their silos strategically dispersed primarily across the vast, often desolate, landscapes of the northern Rocky Mountain states and the Dakotas . These hardened underground bunkers serve as silent sentinels, housing weapons capable of reaching virtually any point on the globe within minutes. The formidable Peacekeeper missiles , once a cornerstone of the U.S. land-based arsenal, were systematically phased out of the Air Force inventory by 2005. Similarly, all USAF Minuteman II missiles were meticulously destroyed in strict accordance with the terms of the START treaty, their launch silos subsequently imploded, buried, and, in a curious footnote to history, even sold to the public under the provisions of START II . Under the SORT treaty, the U.S. had set a goal to significantly reduce its land-based arsenal from 1,600 warheads deployed on over 500 missiles in 2003, to a target of 500 warheads on 450 missiles by 2012. The initial Minuteman III missiles began to be removed under this plan in 2007. Concurrently, in a move that underscored the continuous refinement of destructive capabilities even amidst reduction, the warheads deployed on the remaining Minuteman IIIs commenced an upgrade process, transitioning from the smaller W62s to the considerably more potent W87s , which were repurposed from the decommissioned Peacekeeper missiles [12]. A constant dance of reduction and modernization.

Air-based delivery systems

B-2 Spirit stealth strategic bomber . (A sleek, ominous silhouette against the sky, a reminder that stealth can carry ultimate destruction.)

The U.S. Air Force also maintains a vital component of the nuclear triad: its strategic nuclear bomber fleet. This airborne arm of deterrence consists of 51 nuclear-armed B-52 Stratofortresses , the venerable workhorses of strategic bombing, alongside 20 of the technologically advanced and notoriously expensive B-2 Spirits stealth bombers [17]. In a notable strategic shift, all 64 B-1 Lancer bombers were retrofitted by 2007 to operate exclusively in a conventional combat mode, thereby removing them from the nuclear delivery platform count.

Beyond the dedicated strategic bomber force, the U.S. military retains the capability to deploy smaller, more “flexible” tactical nuclear weapons using its conventional fighter-bombers . The U.S. maintains approximately 400 nuclear gravity bombs specifically designed for deployment by a range of modern fighter aircraft, including the F/A-18 Hornet , F-15E Strike Eagle , F-16 Fighting Falcon , F-22 Raptor , and the F-35 Lightning II [12]. A significant portion of these — some 350 bombs — are not stored domestically but are controversially deployed at seven airbases spread across six European NATO countries [12]. Of these forward-deployed munitions, approximately 180 tactical B61 nuclear bombs fall under the contentious banner of a nuclear sharing arrangement [18], a policy that effectively places U.S. nuclear weapons on the soil of non-nuclear states, a complex and often debated aspect of deterrence strategy.

Submarine-based ballistic missiles

USS Kentucky, an Ohio-class ballistic missile submarine . (A silent leviathan gliding through the deep, carrying a payload capable of ending civilization. A truly inconvenient metaphor for peace.)

The U.S. Navy currently operates a fleet of 18 Ohio-class submarines , considered the pinnacle of strategic deterrence. Of these, 14 are dedicated ballistic missile submarines (SSBNs), each one a mobile, virtually undetectable launch platform. Every SSBN is engineered to carry a maximum complement of 24 Trident II missiles, ensuring an overwhelming retaliatory strike capability. In a move reflecting evolving strategic priorities, approximately 12 U.S. attack submarines were previously equipped to launch nuclear-tipped Tomahawk missiles , but these specific weapons were systematically removed from service by 2013 [19], streamlining the nuclear role primarily to the SSBN fleet. As of 2018 [update], the combined count of Deployed and Non-Deployed SLBMs on the Ohio-Class SSBNs stood at 280, with 203 of these SLBMs actively deployed [17], a testament to the continuous, silent vigilance maintained beneath the world’s oceans.

Biological weapons

Main article: United States biological weapons program

The United States offensive biological weapons program, a chapter of unsettling scientific endeavor, was officially instigated by President Franklin Roosevelt and the U.S. Secretary of War in October 1941, a pragmatic decision born from the exigencies of World War II . Research and development for these insidious agents were conducted at multiple sites across the country. A dedicated production facility was established at Terre Haute, Indiana . However, initial testing with a benign agent revealed unacceptable levels of contamination within the facility, a fortunate, if unintended, setback that prevented any actual biological agent production there during World War II [21].

Perhaps one of the most disturbing aspects of this program was the documented use of civilian populations for clandestine testing of bioweapon effects. In 1950, the U.S. Navy conducted a covert experiment on the unsuspecting civilian populace of the San Francisco Bay Area under the guise of Operation Sea-Spray . Over 800,000 residents were unknowingly sprayed with various pathogens, an act that directly led to at least one recorded death and generated claims of irreversible ecological alterations [22]. In a similarly egregious incident in 1951, the U.S. military released fungal spores at the Norfolk Naval Supply Center, specifically targeting African-American workers, in an abhorrent attempt to assess their susceptibility to the pathogen compared to Caucasians [23]. The experiments continued, with the U.S. government famously releasing Bacillus globigii into the New York City Subway system in 1966. The stated objective was to research the dynamics of pathogen dissemination within a civilian population. However, numerous individuals exposed during this test later reported suffering from long-term medical conditions, a causation the military has steadfastly denied [23]. These unsettling experiments on civilian populations persisted in various cities across the country until the early 1970s, a grim testament to a period of profound ethical disregard.

The Dugway Proving Ground facility in Utah , established in 1942, remains to this day a site for the testing and storage of biological weapons. This sprawling 800,000-acre facility has been implicated in the weaponization of insects, including fleas and mosquitoes, and has reportedly conducted experiments on both animal and, disturbingly, human subjects [24]. A more advanced production facility for biological agents was subsequently constructed in Pine Bluff, Arkansas , commencing operations in 1954. Fort Detrick , Maryland , later expanded its role to become both a primary research hub and an additional production facility. The U.S. program developed a diverse range of anti-personnel and anti-crop biological weapons [25], alongside various sophisticated deployment systems. These included aerial spray tanks, aerosol spray canisters, specialized grenades, rocket warheads, and even cluster bombs, demonstrating a comprehensive effort to integrate biological agents into conventional military doctrine. (For further details, refer to U.S. Biological Weapon Testing ).

E120 biological bomblet , developed before the U.S. ratified the Biological Weapons Convention . (A small, innocuous-looking device designed to spread disease, a chilling example of humanity’s ingenuity in creating new forms of suffering.)

By mid-1969, a shift in international sentiment became apparent, with both the United Kingdom and the Warsaw Pact independently introducing proposals to the UN aimed at banning biological weapons. This diplomatic momentum eventually culminated in a comprehensive treaty in 1972. In a pivotal executive action, the U.S. formally cancelled its offensive biological weapons program through an executive order issued in November 1969 (covering microorganisms) and February 1970 (addressing toxins). This order mandated the complete destruction of all offensive biological weapons, a process that was meticulously carried out between May 1971 and February 1973. The U.S. subsequently ratified the Geneva Protocol on January 22, 1975, and formally ratified the Biological Weapons Convention (BWC) when it came into effect in March 1975 [Kissinger 1969].

Despite these commitments, efforts to establish a legally binding verification protocol to the BWC dragged on for years, a testament to the inherent difficulties in monitoring such elusive weapons. In 2001, these protracted negotiations ultimately collapsed when the Bush administration controversially rejected a collective effort by other signatories to create such a verification mechanism. The administration argued that such a protocol could be susceptible to abuse, potentially interfering with legitimate biological research, a stance that drew considerable criticism for undermining global disarmament efforts.

Today, the U.S. Army Medical Research Institute of Infectious Diseases , located at Fort Detrick , continues to produce small quantities of biological agents. However, according to the U.S. government, this activity is strictly for defensive biological weapons research and is performed in full accordance with the provisions of the BWC. This distinction, while legally sound, does little to fully alleviate the inherent unease surrounding such research.

A stark reminder of the lingering threat posed by biological agents occurred in September 2001, shortly after the September 11 attacks . The United States was gripped by a series of anthrax attacks targeting U.S. media offices and members of the U.S. Senate , which tragically claimed five lives. The specific strain of anthrax utilized in these attacks was identified as the Ames strain , a variant that had originally been studied at Fort Detrick and subsequently distributed to other laboratories around the world, creating a disturbing link between defensive research and offensive capabilities.

Chemical weapons

Main article: United States chemical weapons program

During World War I , a conflict that saw the widespread and horrific introduction of chemical warfare, the U.S. established its own chemical weapons program. This initiative was responsible for the production of various chemical munitions, including the choking agent phosgene and the infamous blistering agent mustard gas [26]. However, in comparison to the other belligerent nations, the U.S. produced a relatively modest amount, accounting for approximately 4% of the total chemical weapons manufactured for that war and just over 1% of the era’s most effective weapon, mustard gas . Consequently, U.S. troops suffered less than 6% of the overall gas casualties experienced during the conflict. Although the U.S. had begun large-scale production of Lewisite , a highly toxic arsenical compound, for an offensive planned in early 1919, the war concluded before Lewisite could be deployed [27][28]. A specialized unit, the 1st Gas Regiment [26], was specifically trained and utilized phosgene in attacks after its deployment to France [29].

Despite the horrors of World War I , chemical weapons were not employed for military purposes by either the Allies or Germany during World War II . Nevertheless, such weapons were indeed deployed to Europe from the United States , a silent, ominous presence. In a tragic and largely suppressed incident in 1943, German bombers attacked the port of Bari in Southern Italy, resulting in the sinking of several American ships. Among these was the John Harvey, which, unbeknownst to most, was secretly carrying a highly classified cargo of mustard gas . The presence of the gas was a tightly guarded secret, and according to the U.S. military’s account, “Sixty-nine deaths were attributed in whole or in part to the mustard gas, most of them American merchant seamen” out of 628 mustard gas military casualties [Navy 2006][Niderost]. This devastating affair was deliberately kept secret at the time and for many years thereafter, a testament to the lengths taken to conceal the darker aspects of wartime logistics. Following World War II , the U.S. simultaneously participated in international arms control discussions concerning chemical weapons while continuing to aggressively stockpile them, eventually amassing an arsenal exceeding 30,000 tons of material.

Honest John missile warhead cutaway, showing M134 Sarin bomblets (photo c. 1960). (A chilling cross-section, revealing the intricate mechanism designed to disperse lethal nerve agents, a testament to a very specific kind of human ingenuity.)

In the aftermath of the war, all of the former Allies embarked on further research into the three new, terrifying nerve agents developed by the Nazis: tabun , sarin , and soman . Over the ensuing decades, during the paranoid intensity of the Cold War , thousands of American military volunteers were subjected to exposure to various chemical agents as part of testing programs, often under dubious ethical pretenses, alongside numerous accidental exposures. One such infamous accident occurred in 1968, when a nerve agent drifted out of Dugway Proving Ground during a test, tragically killing approximately 6,400 sheep [30]. The U.S. also explored a wide array of potential nonlethal, “psychobehavioral” chemical incapacitating agents, delving into substances such as psychedelic indoles like LSD and various marijuana derivatives, as well as several glycolate anticholinergics. One particular anticholinergic compound, 3-quinuclidinyl benzilate , was assigned the NATO code BZ and was weaponized in the early 1960s for potential battlefield use, a truly unsettling attempt to weaponize psychological disruption. Persistent allegations regarding the use of chemical agents by the U.S. in the Korean War (1950–53) have, however, never been conclusively substantiated [31][32][33].

In late 1969, President Richard Nixon made a landmark decision, unilaterally renouncing the first use of chemical weapons, a declaration that extended to all methods of biological warfare as well [34]. He subsequently issued a unilateral decree halting the production and transport of chemical weapons, a directive that, remarkably, remains in effect to this day. From 1967 to 1970, the U.S. engaged in Operation CHASE , a controversial disposal method that involved sinking ships laden with chemical weapons into the deep Atlantic Ocean , a solution that, while expedient, raised significant environmental concerns. Recognizing the need for safer, more responsible disposal, the U.S. began researching improved methods for chemical weapons destruction in the 1970s, successfully destroying several thousand tons of mustard gas through incineration and nearly 4,200 tons of nerve agent via chemical neutralization [35].

The U.S. formally acceded to the Geneva Protocol in 1975, coincident with its ratification of the Biological Weapons Convention . This marked the first operative international treaty on chemical weapons to which the U.S. was a party. Significant stockpile reductions commenced in the 1980s, beginning with the removal of outdated munitions and the complete destruction of the entire stock of BZ, which started in 1988. By 1990, the destruction of chemical agents stored on Johnston Atoll in the Pacific Ocean began, a full seven years before the Chemical Weapons Convention (CWC) officially came into effect. In a notable act of international cooperation, President Ronald Reagan initiated the removal of the U.S. stockpile of chemical weapons from Germany in 1986, an effort known as Operation Steel Box [36].

In 1991, President George H. W. Bush unilaterally committed the U.S. to the complete destruction of all its chemical weapons and, crucially, renounced the right to chemical weapon retaliation, a significant policy shift.

The U.S. signed the CWC in 1993, which imposed a binding requirement for the destruction of all chemical weapon agents, their dispersal systems, and chemical weapons production facilities by 2012. Both Russia and the U.S. , however, notoriously missed the CWC’s extended deadline of April 2012 for the complete destruction of their chemical weapons stockpiles [37]. By the original deadline, the United States had managed to destroy 89.75% of its initial stockpile, which amounted to nearly 31,100 metric tons (or 30,609 long tons ) of nerve and mustard agents under the terms of the treaty [38]. Chemical weapons destruction efforts, after a period of delay, resumed in 2015 [39]. The nation’s final remaining stockpile was located at the Blue Grass Army Depot in Kentucky [40]. In a historic announcement, the U.S. officially destroyed its final declared chemical weapon on July 7, 2023 [41]. The last weapon to be eliminated was a sarin nerve agent -filled M55 rocket , marking the end of a long and costly chapter in military history. The total expense incurred for the entire program to destroy its chemical weapons arsenal ultimately reached an astonishing $40 billion [42], a sum that truly highlights the enduring cost of past strategic decisions.

See also

• Defense Threat Reduction Agency – The U.S. Department of Defense ’s official Combat Support Agency for countering weapons of mass destruction.
• Dugway sheep incident
• Enduring Stockpile – the name of the United States ’s remaining arsenal of nuclear weapons following the end of the Cold War .
• List of U.S. biological weapons topics
• Nuclear weapons and the United States
• Operation Paperclip – the codename under which the U.S. intelligence and military services extricated scientists from Germany, during and after the final stages of World War II .
• Russia and weapons of mass destruction
• Nuclear weapons of the United Kingdom
• United States Army Chemical Corps
• United States missile defense

Notes

• ^ B61 nuclear bombs stored in European NATO countries under nuclear sharing are under the command of United States Air Forces in Europe via munitions squadrons .