A strategic nuclear weapon (SNW) refers to a nuclear weapon that is designed to be used on targets often in settled territory far from the battlefield as part of a strategic plan, such as military bases, military command centers, arms industries, transportation, economic, and energy infrastructure, and countervalue targets such areas such as cities and towns. [1] It is in contrast to a tactical nuclear weapon, which is designed for use in battle as part of an attack with and often near friendly conventional forces, possibly on contested friendly territory. As of 2024, strategic nuclear weapons have been used twice in the 1945 United States bombings of Hiroshima and Nagasaki.
Strategic nuclear weapons generally have significantly larger yields, and typically starting from 100 kilotons up to destructive yields [2] in the low megaton range for use especially in the enemy nation's interior far from friendly forces to maximize damage, especially to buried hard targets, like a missile silo or wide area targets like a large bomber or naval base. However, yields can overlap, and many weapons such as the variable yield B61 nuclear bomb which could be used at low power by a fighter-bomber in an interdiction strike or at high yield dropped by a strategic bomber against an enemy submarine pen. The W89 200 kiloton (0.2 MT) warhead armed both the tactical Sea Lance area effect anti-submarine weapon for use far out at sea and the strategic bomber launched SRAM II stand off missile designed for use in the Soviet Union's interior. The strategic attacks on Hiroshima and Nagasaki utilized weapons of between 10 and 20 kilotons, but that was because the "Little Boy" and "Fat Man" bombs were the most destructive and only nuclear weapons then available. There is no precise definition of the "strategic" category for either range nor yield. [3] [4] The yield of tactical nuclear weapons is generally lower than that of strategic nuclear weapons, but larger ones are still very powerful, and some variable-yield warheads serve in both roles. Modern tactical nuclear warheads have yields up to the tens or potentially hundreds of kilotons, several times that of those used in the atomic bombings of Hiroshima and Nagasaki.
Strategic thinking under the Eisenhower administration and Secretary of State John Foster Dulles was that of massive retaliation in the face of the Soviet Union's nuclear arsenal. The two superpowers developed many of the most destructive deployed thermonuclear weapons. Every bit of destructive power that could be delivered to the enemy's interior was considered advantageous in maintaining deterrence and would become the basis of the US strategic arsenal. [5] Flexible response was a defense strategy first implemented by President John F. Kennedy in 1961 to address the administration's skepticism of the policy of massive retaliation in the face of strike options limited to total war during the Cuban Missile Crisis. [6] That, along with cost, increasingly-accurate targeting, multiple warheads per delivery vehicle, and a desire for greater flexibility in targeting especially with respect to increasing sensitivity to collateral damage in some scenarios, began the trend to reducing individual warhead yields in strategic weapon systems. [7]
Strategic missiles and bombers are assigned preplanned targets including enemy airfields, radars, and surface to air defenses; but the strategic mission was to eliminate the enemy nation's national defenses to allow following strategic bombers and missiles to penetrate and threaten in force the enemy nation's strategic forces, command, population, and economy more realistically, rather than targeting purely military assets in nearly real time using tactical weapons, with range and yield optimized for this type of time-sensitive attack mission often near friendly forces. [1]
Early ICBMs had an unfavorable circular error probable (CEP); the strategic missiles and, in some conditions, bombers had low targeting accuracy. Additionally, much early Cold War strategic asset construction was above-ground soft targets or minimally-hardened such as airfields, pre-nuclear command and control installations, defensive infrastructure, and even ICBM bases. When every missile carried only one poorly-guided warhead designing systems with massive warhead yields to cause a huge damage footprint, with the possibility of potentially destroying several nearby soft targets of opportunity and increasing the likelihood that the primary target was within the overlap of CEP and destruction circle the highest possible yield warhead for the missile was considered an advantage. [8] The enemy being targeted a continent away was a low ratio of side effects to friendly areas, which contrasted the potential damage to enemy assets. As navigation technology improved the accuracy and many missiles and nearly all bombers were equipped with multiple nuclear warheads the trend was to reduce warhead yield both for weight and to give more flexibility in targeting with respect to collateral damage, target hardening also created a situation in which even a very large warhead with excellent targeting would still destroy only one target, gaining no advantage to its large weight and expense, as opposed to several smaller MIRVs. [9]
A feature of strategic nuclear weapons, especially in the transcontinental nature of the Cold War, with continent-spanning superpowers that are oceans apart, is the greater range of their delivery apparatus, such as ICBMs, giving them the ability to threaten the enemy's command and control structure and national infrastructure even though they were based many thousands of miles away in friendly territory. ICBMs with nuclear warheads are the primary strategic nuclear weapons, and short-range missiles are tactical. In addition, while tactical weapons are designed to meet battlefield objectives without destroying nearby friendly forces, one main purpose of strategic weapons is deterrence under the theory of mutually assured destruction. In the case of two small bordering nations, a strategic weapon could have a quite short range and still be designed or intended for strategic targeting. Specifically, on the Korean Peninsula, with a nuclear-armed North Korea facing off against an NPT-compliant South Korea there have been calls to request a return of US-owned short range low yield nuclear weapons, nomenclatured as tactical by the US military, to provide a local strategic deterrent to the North's growing domestically produced nuclear arsenal and delivery systems. [10]
After the Cold War, the tactical nuclear weapon stockpiles of NATO and Russia were greatly reduced. Highly-accurate strategic missiles like the Trident II can also be used in substrategic, tactical strikes.
According to several reports, including by the Carnegie Endowment for International Peace and Bulletin of the Atomic Scientists, as a result of the effectiveness and acceptability of United States Air Force use of precision munitions with little collateral damage in the Kosovo conflict in what amounted to strategic destruction once only possible with nuclear weapons or massive bombing, Vladimir Putin, then-secretary of the Security Council of Russia, formulated a concept ("escalate to de-escalate") of using both tactical and strategic nuclear threats and strikes to de-escalate or cause an enemy to disengage from a conventional conflict threatening what Russia considers a strategic interest. [11] [12] [13] The lowered threshold for use of nuclear weapons by Russia is disputed by other experts. [14] [15]
Nuclear warfare, also known as atomic warfare, is a military conflict or prepared political strategy that deploys nuclear weaponry. Nuclear weapons are weapons of mass destruction; in contrast to conventional warfare, nuclear warfare can produce destruction in a much shorter time and can have a long-lasting radiological result. A major nuclear exchange would likely have long-term effects, primarily from the fallout released, and could also lead to secondary effects, such as "nuclear winter", nuclear famine, and societal collapse. A global thermonuclear war with Cold War-era stockpiles, or even with the current smaller stockpiles, may lead to various scenarios including the human extinction.
In nuclear strategy, a first strike or preemptive strike is a preemptive surprise attack employing overwhelming force. First strike capability is a country's ability to defeat another nuclear power by destroying its arsenal to the point where the attacking country can survive the weakened retaliation while the opposing side is left unable to continue war. The preferred methodology is to attack the opponent's strategic nuclear weapon facilities, command and control sites, and storage depots first. The strategy is called counterforce.
Mutual assured destruction (MAD) is a doctrine of military strategy and national security policy which posits that a full-scale use of nuclear weapons by an attacker on a nuclear-armed defender with second-strike capabilities would result in the complete annihilation of both the attacker and the defender. It is based on the theory of rational deterrence, which holds that the threat of using strong weapons against the enemy prevents the enemy's use of those same weapons. The strategy is a form of Nash equilibrium in which, once armed, neither side has any incentive to initiate a conflict or to disarm.
The LGM-30 Minuteman is an American land-based intercontinental ballistic missile (ICBM) in service with the Air Force Global Strike Command. As of 2024, the LGM-30G is the only land-based ICBM in service in the United States and represents the land leg of the U.S. nuclear triad, along with the Trident II submarine-launched ballistic missile (SLBM) and nuclear weapons carried by long-range strategic bombers.
A multiple independently targetable reentry vehicle (MIRV) is an exoatmospheric ballistic missile payload containing several warheads, each capable of being aimed to hit a different target. The concept is almost invariably associated with intercontinental ballistic missiles carrying thermonuclear warheads, even if not strictly being limited to them. An intermediate case is the multiple reentry vehicle (MRV) missile which carries several warheads which are dispersed but not individually aimed. All nuclear-weapon states except Pakistan and North Korea are currently confirmed to have deployed MIRV missile systems. Israel is suspected to possess or be in the process of developing MIRVs.
A nuclear bunker buster, also known as an earth-penetrating weapon (EPW), is the nuclear equivalent of the conventional bunker buster. The non-nuclear component of the weapon is designed to penetrate soil, rock, or concrete to deliver a nuclear warhead to an underground target. These weapons would be used to destroy hardened, underground military bunkers or other below-ground facilities. An underground explosion releases a larger fraction of its energy into the ground, compared to a surface burst or air burst explosion at or above the surface, and so can destroy an underground target using a lower explosive yield. This in turn could lead to a reduced amount of radioactive fallout. However, it is unlikely that the explosion would be completely contained underground. As a result, significant amounts of rock and soil would be rendered radioactive and lofted as dust or vapor into the atmosphere, generating significant fallout.
The Single Integrated Operational Plan (SIOP) was the United States' general plan for nuclear war from 1961 to 2003. The SIOP gave the President of the United States a range of targeting options, and described launch procedures and target sets against which nuclear weapons would be launched. The plan integrated the capabilities of the nuclear triad of strategic bombers, land-based intercontinental ballistic missiles (ICBM), and sea-based submarine-launched ballistic missiles (SLBM). The SIOP was a highly classified document, and was one of the most secret and sensitive issues in U.S. national security policy.
The B83 is a variable-yield thermonuclear gravity bomb developed by the United States in the late 1970s that entered service in 1983. With a maximum yield of 1.2 megatonnes of TNT (5.0 PJ), it has been the most powerful nuclear weapon in the United States nuclear arsenal since October 25, 2011 after retirement of the B53. It was designed by Lawrence Livermore National Laboratory.
The B61 nuclear bomb is the primary thermonuclear gravity bomb in the United States Enduring Stockpile following the end of the Cold War. It is a low-to-intermediate yield strategic and tactical nuclear weapon featuring a two-stage radiation implosion design.
The Enduring Stockpile is the United States' arsenal of nuclear weapons following the end of the Cold War.
The AGM-131 SRAM II was a nuclear air-to-surface missile intended as a replacement for the AGM-69 SRAM. The solid-fueled missile was to be dropped from a B-1B Lancer, carry the W89 warhead and have a range of 400 km. However, the program was canceled by President George H. W. Bush for geopolitical reasons just as the first flight-test missile was delivered.
The United States was the first country to manufacture nuclear weapons and is the only country to have used them in combat, with the bombings of Hiroshima and Nagasaki in World War II. Before and during the Cold War, it conducted 1,054 nuclear tests, and tested many long-range nuclear weapons delivery systems.
The W85 was a thermonuclear warhead developed by the United States of America to arm the Pershing II missile. It was a variable yield device with a selectable yield of 0.3, 5, 10 or 80 kilotonnes of TNT.
Nuclear weapons delivery is the technology and systems used to place a nuclear weapon at the position of detonation, on or near its target. Several methods have been developed to carry out this task.
A tactical nuclear weapon (TNW) or non-strategic nuclear weapon (NSNW) is a nuclear weapon that is designed to be used on a battlefield in military situations, mostly with friendly forces in proximity and perhaps even on contested friendly territory. Generally smaller in explosive power, they are defined in contrast to strategic nuclear weapons, which are designed mostly to be targeted at the enemy interior far away from the war front against military bases, cities, towns, arms industries, and other hardened or larger-area targets to damage the enemy's ability to wage war. As of 2024, no tactical nuclear weapons have ever been used in combat.
The B61 Family is a series of nuclear weapons based on the B61 nuclear bomb.
A nuclear triad is a three-pronged military force structure of land-based intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and strategic bombers with nuclear bombs and missiles. Countries build nuclear triads to eliminate an enemy's ability to destroy a nation's nuclear forces in a first-strike attack, which preserves their own ability to launch a second strike and therefore increases their nuclear deterrence.
A high-alert nuclear weapon commonly refers to a launch-ready ballistic missile that is armed with a nuclear warhead whose launch can be ordered and executed within 15 minutes. It can include any weapon system capable of delivering a nuclear warhead in this time frame.
In nuclear strategy, a counterforce target is one that has a military value, such as a launch silo for intercontinental ballistic missiles, an airbase at which nuclear-armed bombers are stationed, a homeport for ballistic missile submarines, or a command and control installation.