NATO will receive new tactical nuclear weapons. Questions abound regarding their role
In a hypothetical scenario part of a Russian Army KBM 9K720 Iskander-M Short-Range Ballistic Missile (SRBMs) brigade stationed in Russia’s European Kaliningrad enclave has dispersed into the field and deployed in the vicinity of Pravdinks; a town close to the border with Poland. The deployment follows several days of border skirmishes between Russian forces, and Polish and NATO troops on the Polish-Kaliningrad border. NATO intelligence reveals that the 9K720 SRBMs are each equipped with a 50 kiloton/kt (one kiloton is equal to 1,000 tonnes of conventional explosive) warhead and are preparing to perform a counterforce strike against Polish and NATO ground forces with a view to easing the path of Russian Army units. These units will perform a limited invasion of northeast Poland with a view to forcing NATO to withdraw its land forces helping to defend the Baltic states and other areas directly adjacent to the border of European Russia. NATO takes the decision to dissuade Russia from this course of action by ordering a signal nuclear strike using US-supplied B-61 Mod.3/4 freefall nuclear bombs which are supplied to NATO by the US, but which are delivered by the combat aircraft of European NATO members (see below). A single airburst detonation of 60 kilotons (the B-61 Mod.3/4 is a variable yield weapon) is performed at an altitude of 200 feet (61 metres) destroying the 9K720, but undoubtedly gravely escalating the conflict.
The Cold War
It may surprise a number of readers to know that NATO maintains a force of so-called tactical nuclear weapons which are supplied to the alliance by the US, maintained on European airbases under US custody but which would be released to NATO for use in times of war or heightened international tension. The US Department of Defence (US DOD) defines tactical nuclear weapons employment as “the use of nuclear weapons by land, sea and air forces against opposing forces, supporting installations or facilities in support of operations which contribute to the accomplishment of a military mission of limited scope, or in support of the military commander’s scheme of manoeuvre usually limited to the area of military operations.”
Freefall nuclear bombs played a major role in NATO’s operational nuclear posture during the Cold War. William Arkin and Richard Fieldhouse’s seminal 1985 work Nuclear Battlefields: Global Links in the Arms Race, stated that of the circa 3,000 nuclear warheads which the US forward-deployed to Europe during the latter stages of the Cold War, 1,700 of these were freefall nuclear bombs. During the Cold War, the authors continue, NATO would have placed a priority on the destruction of mobilised Soviet/Warsaw Pact forces which could include the manoeuvre forces themselves, their headquarters and logistics. Other options included the use of nuclear bombs to target geographical features or ‘choke points’ to frustrate the ability of the manoeuvre force to use terrain to its advantage. In airpower terms, such targeting was known then, as it is know, as air interdiction. This process is defined by the US DOD as any air operations “conducted to destroy, neutralize, or delay the enemy’s military potential before it can be brought to bear effectively against friendly forces.” This is distinct from the close air support role, hardly something that would be practical using nuclear weapons as air interdiction is conducted “at such distance from friendly forces that detailed integration of each air mission with the fire and movement of friendly forces is not required.”
Beyond the targeting of manoeuvre forces air interdiction, during the Cold War the use of such weapons at the operational level would have included attacks against ammunition dumps and weapons storage areas, airbases, POL (Petroleum, Oil, Lubricants) storage areas; storage and accommodation facilities for materiel and personnel; railway marshalling yards, bridges and rail, road and waterway chokepoints in the Warsaw Pact and the European Soviet Union across the Inner German Border. As Arkin and Fieldhouse noted, NATO war plans would have called for the use of tactical nuclear weapons against mobile Soviet nuclear forces the European Theatre of Operations chiefly RSD-10 Dvina (NATO reporting name SS-20 Sabre) medium-range ballistic missiles and the 9M21B Luna-M (NATO reporting name FROG-7) nuclear-tipped short-range artillery system. Aircraft-delivered tactical nuclear weapons such as the B-61 series would be highly appropriate for such targets given the ability of their delivery systems to rapidly change from briefed targets to targets of opportunity, or briefed targets that have changed location, while in flight.
Although the B-61 debuted in service in the early 1970s the weapon remains in service today and is undergoing an upgrade. As a result the United States is performing a wholesale rejuvenation of its nuclear arsenal which includes the upgrade of legacy B-61 weapons to the B-61 Mod.12 status. This includes the refurbishment of the weapons’ nuclear warheads, and improved security systems to prevent their unauthorised use. The programme to overhaul these bombs (both those provided to NATO, and those deployed by the US armed forces) is expected to cost $10 billion, according to the Washington DC-based Arms Control Association with the initiative, which will give the bombs an extra three decades of life, expected to be completed in 2025. The development of the B-61 Mod.12 includes a number of organisations namely the Sandia National and Los Alamos National Laboratories, both of which are thought to be involved with the overall design of the weapon and its physics package; Boeing which builds the B-61 Mod.12’s tails assembly under contract from the US Air Force Nuclear Weapons Centre, and the Nuclear Security Enterprise which is tasked with the weapon’s manufacture. Current US government plans call for up to 500 B-61 Mod.12 examples to be manufactured. The weapon is expected to have a variable yield of up to 50kt and to have earth penetration capabilities to hit buried targets.
Despite the upgrade, there are questions as to the utility of such weapons in any future conflict, particularly in the European Theatre. Professor Christopher Bellamy, Chair of Military Science and Doctrine, and Director of the Security Studies Institute at the University of Cranfield in southern England, wrote in 2001 that “the development of Precision Guided Munitions (PGMs) and improved area conventional munitions has arguably made battlefield nuclear weapons obsolete … Conventional bombs (are) able to strike their targets so accurately they could perform the same military tasks as nuclear weapons.” Certainly, Boeing’s Joint Direct Attack Munition series of GPS (Global Positioning System) guided air-to-ground satellite navigation kits can turn an unguided ‘dumb’ weapon into ordnance with a published accuracy of at least 13 metres (42.7 feet).
One of the attractions of tactical nuclear weapons, or any nuclear weapon for that matter, was that their destructive radius would be so large as to render pinpoint accuracy a secondary consideration. As a means of comparison, a simple simulation using the nuclearsecrecy.com website which simulates the effect of various nuclear weapons shows that an airburst detonation of a B-61 Mod.3 weapon generates overpressures of up to five pounds-per-square inch across a 75.6 square kilometre (29.1 square mile) range. Such overpressures are sufficient to destroy residential buildings, cause widespread fatalities and widespread injuries. Thus, even detonating such a weapon four kilometres (2.5 miles) away from its intended aim point will almost certainly cause significant damage if that target is a bridge or marshalling yard, for example. The Persian Gulf War of 1991 indicated that targets such as bridges could be comprehensively destroyed by PGMs deployed by the US-led coalition assembled to evict Iraqi from Kuwait. Official records stated that 41 of 54 key Iraqi bridges were destroyed using PGMs.
While the B-61 series’ mission was arguably clear during the Cold War the advent of PGMs has changed its role despite the advent of the so-called new ‘Cold War’ a term which has been in existence since the eruption of tensions between NATO and Russia in the wake of the Ukraine crisis of November 2013. Nevertheless, as the upgrade initiative for the B-61 indicates, neither NATO nor the US appear likely to decommission the weapon in the near future.
Current US nuclear weapons plans, as outlined in the Nuclear Posture Review, published in February which details the place of the country’s nuclear weapons in the nation’s wider national security strategy, stipulates that the country will maintain the B-83 Mod.1 variable-yield (low kiloton to 1.2 megaton) gravity bomb and the B-61 Mod.3 variable-yield (0.3kt, 1.5kt, 60kt or 170kt) weapons in service until “there is sufficient confidence” in the B-61 Mod.12 for it to assume the role of these weapons “to hold at risk a variety of protected targets.” The review continues that the B-61 Mod.12 is expected to become available from 2020. The US also sees the weapon’s role as “a key contributor to continued regional deterrence stability and the assurance of allies.” In the non-strategic role, these weapons in US service will be delivered by Boeing F-15E Strike Eagle ground attack aircraft, and later the Lockheed Martin F-35A Block-IV Lightning-II jets of the US Air Force (with reports stating that no plans exist to certify the B-61 Mod.12 on the F-35B/C jets being acquired by the US Marine Corps and US Navy), with the F-35A expected to be certified to carry the weapon by 2022 at the latest. The review continues that the B-61 Mod.12 will start replacing the existing B-61 Mod.3/4 in the NATO inventory from 2021. Open source reports estimate that the US deploys between 150 and 200 B-61 Mod.3/4 weapons to a total of six airbases in Belgium (Kleine Bogel, General Dynamics/Lockheed Martin F-16AM Fighting Falcon), Germany (Büchel, Panavia Tornado-IDS), Italy (Aviano and Ghedi Torre, Panavia Tornado-IDS) and the Netherlands (Volkel, F-16AM), with between ten and 20 weapons thought to be stored at each site. Moreover, the US may also stockpile B-61 weapons at Incirlik airbase in the south of Turkey where between 50 and 70 examples weapons maybe stored for use by US combat aircraft.
Despite the end of the Cold War, NATO still sees some utility in retaining US-supplied nuclear weapons. The April 2012 US Army Strategic Studies Institute publication Tactical Nuclear Weapons and NATO states that the Alliance views such weapons “as a deterrent to any potential adversary, and … as a link among the NATO nations, through shared responsibility for nuclear policy planning and decision-making,” continuing that such weapons “also serve as a visible reminder of the US extended deterrent and assurance of its commitment to the defence of its allies.” This chimes with an official statement provided to MONch by NATO which stated that “the strategic forces of allies, particularly those of the United States, are the supreme guarantee of our collective security. The nuclear forces of the United Kingdom and France also contribute to our overall security.”
However, Maxwell Downman of the British and American Security Information Council, a research organisation based in London, questions where the B-61 still has a military role, arguing that the weapon now carries more political, than military, significance. “The B-61 is commonly regarded as part of the ‘glue’ that helps hold NATO together, and symbolises the US security commitment to Europe.” He adds that the weapon also presents “options” to the US and NATO as a whole regarding Russian strategic posturing and can be used to “deter limited nuclear strikes with limited nuclear strikes, signalling the willingness to use these weapons below the strategic threshold in a non-strategic environment.” Moreover, as the Nuclear Posture Review stipulates, the US is planning the modification “of a small number of existing (Submarine-Launched Ballistic Missile) warheads to provide a low-yield option,” the document states, alongside the realisation of a nuclear-armed sea-launched cruise missile. This would seem to supplement, if not potentially replace, the role of the B-61 Mod.12 as a sub-strategic weapon.
Yet the continued possession of these weapons, and their presence in some NATO nations, remains controversial. For example, in January 2014, the Dutch government confirmed that the F-35A aircraft it will procure from the United States will have a nuclear role and thus deliver the B-61 Mod.12. This was in spite of a 2012 parliamentary motion which saw the majority of lawmakers opposing a nuclear role for the jet. “Europeans who have seen (the B-61 series) as the glue that helps to hold NATO together will be very worried if the US sees these weapons being used in limited retaliatory strikes.” Mr. Downman adds, noting that there are a number of hurdles which do militate against their utility during an actual conflict: “You have to allow the US to release the codes to arm the weapon, get permission (to use the weapon) from the host nation where the weapons are stored, fit the bomb to the aircraft, take off and fly through air space which will be contested by the Russians and then deliver the bomb to the target.” There is an implicit acknowledgement of the controversies generated in Europe by the B-61 series with the Nuclear Posture Review responding to such concerns by stating that the new SLBM and sea-launched cruise missile which are under consideration will, unlike the NATO-delivered B-61s, “not require or rely on host nation support to provide deterrent effect.”
Furthermore, revisiting estimations made during the Cold War by Arkin and Fieldhouse, only 60 percent of an attacking force of nuclear-armed aircraft would have succeeded in reaching their targets in the event of a full-scale armed conflict with Russia. “Russia has said that it does not regard the B-61 Mod.3 as a military threat at the moment,” Mr. Downman observes, although he cautions that the advent of the B-61 Mod.12 teamed with the F-35A which will have a notably lower radar cross section than the F-16, Tornado-IDS and F-15E jets currently tasked with delivering the B-61 Mod.3, could change Russia’s views in this respect. Therefore, the B-61 Mod.12 could become a divisive and controversial weapon in terms of both European and Russian perceptions of its intended role.