Nuclear triad

Traditional components of a strategic nuclear triad

While traditional nuclear strategy holds that a nuclear triad provides the best level of deterrence from attack, in reality, most nuclear powers do not have the military budget to sustain a full triad. Only the United States and Russia have maintained nuclear triads for most of the nuclear age. Both the US and the Soviet Union composed their triads along the same lines, including the following components:

1. Bomber aircraft capable of delivering nuclear bombs (carrier-based or land-based; usually armed with long-range missiles).
2. Land-based missiles (MRBMs or ICBMs).
3. Ballistic missile submarines (SSBNs). Nuclear missiles launched from ships or submarines. Although in early years the US Navy sea leg was carrier aircraft based with a very short period using sub launched cruise missiles such as the Regulus before SLBMs were ready to be deployed.

The triad also gives the commander in chief the flexibility to use different types of weapons for the appropriate strike while also preserving a reserve of nuclear armaments theoretically safe from a counter-force strike:

Tactical nuclear weapons are used in air, land and sea warfare. Air-to-air missiles and rockets, surface-to-air missiles, and small air-to-ground rockets, bombs, and precision munitions have been developed and deployed with nuclear warheads. Ground forces have included tactical nuclear artillery shells, surface-to-surface rockets, land mines, medium and small man-packable nuclear engineering demolition charges, even man-carried or vehicle-mounted recoilless rifles. Naval forces have carried nuclear-armed naval rocket-assisted and standard depth charges and torpedoes, and naval gunnery shells. Tactical nuclear weapons and the doctrine for their use is primarily for use in a non-strategic warfighting role destroying military forces in the battle area; they are not counted toward triad status despite the possibility of many of these systems being usable as strategic weapons depending on the target.

Triad powers

The following nations are considered fully established triad nuclear powers, they have robust capability to launch a worldwide second strike in all three legs and can disperse their air forces and their sea forces on deterrent patrols. They possess nuclear forces consisting of land-based missiles, ballistic or long-range cruise missile submarines, and strategic bombers or long-range tactical aircraft.

China

Unlike the United States and Russia where strategic nuclear forces are enumerated by treaty limits and subject to verification, China, a nuclear power since 1964, is not subject to these requirements but currently has a triad structure smaller in size compared to Russia and the United States. China's nuclear force is much smaller than the US or Russia and is closer in number and capability to that of France or the United Kingdom. This force is mainly land-based missiles including ICBMs, IRBMs, and tactical ballistic missiles as well as cruise missiles. Unlike the US and Russia, China stores many of its missiles in huge underground tunnel complexes; U.S. Representative Michael Turner referring to 2009 Chinese media reports said "This network of tunnels could be in excess of 5,000 kilometers (3,110 miles), and is used to transport nuclear weapons and forces," the Chinese Army newsletter calls this tunnel system an Underground Great Wall of China.

Currently China has one Type 092 submarine that is currently active with JL-1 SLBM according to Office of Naval Intelligence. In addition, the PLAN has deployed 4 newer Type 094 submarines and plan to deploy up to 8 of these Jin-class SSBN by the end of 2020. The new Type 094 fleet uses the newer JL-2 SLBM. China carried out a series of successful JL-2 launches in 2009, 2012 and 2015. The United States expect the 094 SSBN to carry out its first deterrent patrol by 2015 with the JL-2 missile active. There is an aged albeit upgraded bomber force consisting of Xian H-6s with an unclear nuclear delivery role. The PLAAF has a limited capability fleet of H-6 bombers modified for aerial refuelling as well as forthcoming Russian Ilyushin Il-78 aerial refuelling tankers. China also introduced a newer and modernized H-6 variant the H-6K with enhanced capabilities such as launching long ranged cruise missile the CJ-10. In addition to the H-6 bomber, there are numerous tactical fighter and fighter bombers such as the: J-16, J-10, JH-7A and Su-30 which all capable of carrying nuclear weapons.

India

India completed its nuclear triad with the commissioning of INS Arihant in August 2016. INS Arihant is a nuclear-powered ballistic missile submarine armed with 12 K-15 missiles with a range of 750 km, which will later be upgraded K-4 missiles with an extended range of 3500 km. India maintains a no first use nuclear policy and has been developing a nuclear triad capability as a part of its credible minimum deterrence doctrine. India's nuclear-weapons program possesses surface-to-surface missiles such as the Agni III and Agni IV. In addition, the 5,000–8000 km range Agni-V ICBM was also successfully tested for third time on 31 January 2015 and is expected to enter service by 2016. India has nuclear-capable fighter aircraft such as the Dassault Mirage 2000H, Dassault Rafale, Sukhoi Su-30 MKI, MIG-29 and SEPECAT Jaguar. Land and air strike capabilities are under the control of Strategic Forces Command which is a part of Nuclear Command Authority.

Russia

Also a nuclear power, Russia inherited the arsenal of all of the former Soviet states; this consists of silo-based as well as rail and road mobile ICBMs, sea-based SLBMs, strategic bombers, strategic aerial refueling aircraft, and long-range tactical aircraft capable of carrying gravity bombs, standoff missiles, and cruise missiles. The Russian Strategic Rocket Forces have ICBMs capable of delivering nuclear warheads, silo-based R-36M2 (SS-18), silo-based UR-100N (SS-19), mobile RT-2PM "Topol" (SS-25), silo-based RT-2UTTH "Topol M" (SS-27), mobile RT-2UTTH "Topol M" (SS-27), mobile RS-24 "Yars" (SS-29) (Future replacement for R-36 & UR-100N missiles). Russian strategic nuclear submarine forces are equipped with the following SLBM's, R-29R "Vysota", NATO name SS-N-18 "Stingray", RSM-54 R-29RMU "Sineva", NATO name SS-N-23 "Skiff" and the R-29RMU2.1 "Liner" are in use with the Delta-class submarine, but the RSM-56 R-30 "Bulava", NATO name SS-NX-32 is under development for the Borei-class submarine. The Russian Long Range Aviation operates supersonic Tupolev Tu-22M, and Tupolev Tu-160 bombers and the long range turboprop powered Tupolev Tu-95, they are all mostly armed with strategic stand off missiles or cruise missiles such as the KH-15 and the KH-55/Kh-102. These bombers and nuclear capable strike aircraft such as the Sukhoi Su-24 are supported by Ilyushin Il-78 aerial refuelling aircraft. The USSR was required to destroy its stock of IRBMs in accordance with the INF treaty.

United States

The United States operates Minuteman ICBMs from underground hardened silos, Trident SLBMs carried by Ohio-class submarines, it also operates B-52, B-2 strategic bombers, as well as land-based tactical aircraft, some capable of carrying strategic and tactical B61 and large strategic B83 gravity bombs, and AGM-86 ALCMs. While the US no longer keeps nuclear armed bombers on airborne alert, it has the ability to do so, along with the airborne nuclear command and control aircraft with its fleet of KC-10 and KC-135 aerial refueling planes. Previous to development of submarine-launched ballistic missiles, the US Navy strategic nuclear role was provided by aircraft carrier–based bombers and, for a short time, submarine-launched cruise missiles. With the end of the cold war, the US never deployed the rail-mobile version of the Peacekeeper ICBM or the road mobile Midgetman small ICBM. The US destroyed its stock of road-mobile Pershing II IRBMs and ground-launched cruise missiles in accordance with the INF treaty. The US also has shared strategic nuclear weapons and still deploys shared tactical nuclear weapons to some NATO countries.

France

A former triad power, the French Force de frappe possesses sea-based and air-based nuclear forces through the Triomphant-class ballistic missile submarines deployed with M45 intercontinental SLBMs armed with multiple warheads, nuclear capable Dassault Rafale F3 and Dassault Mirage 2000N fighter aircraft (armed with Air-Sol Moyenne Portée) which replaced the long-range Dassault Mirage IV supersonic nuclear bomber and KC-135 aerial refuelling tankers in its inventory. France had S2 and then S3 silo based strategic nuclear IRBMs, the S3 with a 3,500 km range, but these have been phased out of service since the dissolution of the USSR. France operates aircraft with a nuclear strike role from its aircraft carrier.

Non-triad powers

Non-triad powers are nuclear armed nations which have never developed a strategic nuclear delivery triad.

North Korea

North Korea has claimed to have indigenous nuclear weapons technology since a large underground explosion was detected in 2006. The DPRK has both aircraft and missiles which may be tasked to deliver nuclear weapons. The North Korean missile program is largely based on domestically produced variants of the Soviet Scud missile, some of which are sufficiently powerful to attempt satellite launch. The DPRK also has short-range ballistic missiles and cruise missiles. Western researchers believe the current generation of the DPRK's suspected nuclear weapons are too large to be fitted to the country's existing missile stock.

Pakistan

Pakistan does not have an active nuclear triad. Its nuclear weapons are primarily land-based. The Minimum Credible Deterrence (MCD) is a defense and strategic principle on which the atomic weapons program of Pakistan is based. This doctrine is not a part of the nuclear doctrine, which is designed for the use of the atomic weapons in a full-scale declared war if the conditions of the doctrine are surpassed. Instead, the MCD policy falls under minimal deterrence as an inverse to Mutually Assured Destruction (MAD). In August 2012, The Economist magazine wrote an article stating that Pakistan was an emerging nuclear triad state. Pakistani plans of responding to any capture or pre-emptive destruction of their nuclear defences seems to be one reason why they are determined to develop a third leg, after air- and land-based delivery systems, to Pakistan’s nuclear triad, consisting of nuclear-armed ships and submarines. As Iskander Rehman of the Carnegie Endowment, a think-tank, observes in a recent paper, Pakistani nuclear expansion and methods of delivery is drifting "from the dusty plains of the Punjab into the world’s most congested shipping lanes... It is only a matter of time before Pakistan formally brings nuclear weapons into its own fleet."

Pakistan possesses several ballistic missiles such as the Shaheen-1A and the Shaheen-II, missiles having ranges of 900 km and 2000 km respectively. They also contain systems said to be capable of carrying several nuclear warheads as well as being designed to evade missile-defense systems. Pakistan also possesses the Babur cruise missile with a range up to 700 km. These land-based missiles are controlled by Army Strategic Forces Command of the Pakistan Army.

The PAF has two dedicated units (the No. 16 Black Panthers and the No. 26 Black Spiders) operating 18 aircraft in each squadron of the JF-17 Thunder, believed to be the preferred vehicle for delivery of nuclear weapons. These units are a major part of the Air Force Strategic Command, a command responsible for nuclear response. The PAF also operates a fleet of F-16 fighters, of which 18 were delivered in 2012 and, as confirmed by General Ashfaq Parvez Kayani, are capable of carrying nuclear weapons. The PAF also possesses the Ra'ad air-launched cruise missile which has a range of 350 km and can carry a nuclear warhead with a yield of between 10 kilotons to 35 kilotons.

In 2004, the Pakistan Navy established the Naval Strategic Forces Command and made it responsible for countering and battling naval-based weapons of mass destruction. It is believed by most experts that Pakistan is developing a sea-based variant of the Hatf VII Babur, which is a nuclear-capable ground-launched cruise missile.

United Kingdom

The UK never rolled out its own land based missile nuclear delivery system. It only possesses sea-based nuclear forces through its Royal Navy Vanguard-class ballistic missile submarines, deployed with Trident II intercontinental SLBMs armed with multiple warheads. The Royal Air Force used to operate V bomber strategic bombers throughout the Cold War and continued airborne delivery using Tornado and Jaguar aircraft until the late 1990s. The planned UK silo-based IRBM, the Blue Streak missile, was cancelled as it was not seen as a credible deterrent, considering the population density of areas in the UK geologically suited for missile silos. The tactical Corporal surface-to-surface missile was operated by the British Army. The American made intermediate range Thor missile aimed at Soviet targets was operated briefly by the RAF but before the arrival of the Polaris SLBM. Previously having a nuclear strike mission for carrier-based Buccaneer attack aircraft and later Sea Harriers, the UK no longer deploys nuclear weapons for delivery by carrier-based naval aircraft or any other means other than the Vanguard submarine-launched Trident SLBM.

Suspected triad powers

Israel has been reported in congressional testimony by the US Department of Defense of having aircraft-delivered nuclear weapons as early as the mid-1960s, a demonstrated missile-based force since the mid-1960s, an IRBM in the mid-1980s, an ICBM in the early 2000s and the suspected second-strike capability arrived with the Dolphin-class submarine and Popeye Turbo submarine-launched cruise missile. Israel is suspected of using their inventory of nuclear-capable fighter aircraft such as the long-range F-15E Strike Eagle, F-16 and formerly the F-4 Phantom, Dassault Mirage III, A-4 Skyhawk and Nesher. Israel has appreciable and growing numbers of long-range tanker aircraft and aerial refueling capacity on its long-range fighter-bomber aircraft, this capacity was used in the 1985 long-range conventional strike against the PLO in Tunisia. Jane's Defence Weekly reports that the Israeli Dolphin-class submarines are widely believed to be nuclear armed, offering Israel a second-strike capability with a demonstrated range of at least 1500 km in a 2002 test. According to an official report which was submitted to the American congress in 2004, it may be that with a payload of 1,000 kg the Jericho 3 gives Israel nuclear strike capabilities within the entire Middle East, Africa, Europe, Asia and almost all parts of North America, as well as within large parts of South America and North Oceania, Israel also has the regional reach of its Jericho 2 IRBM force. The existence of a nuclear force is often hinted at blatantly and evidence of an advanced weapons program including miniaturized and thermonuclear devices has been presented, especially the extensive photographic evidence given by former Israeli nuclear weapons assembler Mordechai Vanunu. There have been incidents where Israel has been suspected of testing, but so far Israel for diplomatic reasons has not openly admitted to having operational nuclear weapons, and so is only a suspect triad state.

Other nuclear delivery systems

There is nothing in nuclear strategy to mandate only these three delivery systems. For example, orbital weapons or spacecraft for purposes of orbital bombardment using nuclear devices have been developed and silo deployed by the USSR from 1969 to 1983, these would not fit into the categories listed above. However, actual space-based weapon systems used for weapons of mass destruction have been banned under the Outer Space Treaty and launch ready deployment for the US and former USSR by the SALT II treaty. Another example is the US, UK, and France do or have previously included a strategic nuclear strike mission for carrier-based aircraft, which especially in the past were far harder to track and target with ICBMs or strategic nuclear bombers than fixed bomber or missile bases, permitting some second-strike flexibility; this was the first sea-based deterrent before the SLBM. The US and UK jointly explored an air-launched strategic ballistic nuclear missile, the Skybolt, but canceled the program in favor of submarine-based missiles. In 1974 a Lockheed C-5 Galaxy successfully tested an air launch of a Minuteman ICBM; this system was not deployed, but was used as a bargaining point in the SALT treaty negotiations with the USSR.