Jim Hacker: I don't want to obliterate the whole of Eastern Europe!
Sir Humphrey: But it's a deterrent!
Jim Hacker: It's a bluff, I probably wouldn't use it.
Sir Humphrey: Yes, but they don't know that you probably wouldn't.
Jim Hacker: They probably do.
Sir Humphrey: Yes, they probably know that you probably wouldn't but they can't certainly know!
Jim Hacker: They probably certainly know that I probably wouldn't.
Sir Humphrey: Yes, but even though they probably certainly know that you probably wouldn't, they don't certainly know that, although you probably wouldn't, there is no probability that you certainly would.
Jim Hacker: [beat] ...What?
Cold War and present nuclear strategy, with the ideas underpinning it. The title, despite sounding rather like a Robert Ludlum novel, was a part of British nuclear thinking and the reason for the Chevaline upgrade to Polaris. It basically meant: retain the ability to destroy Moscow.
The ability of one nuclear power to destroy another and only receive an "acceptable" level of losses from nuclear attack yourself. It basically requires the ability to: (a) eliminate command and control functions, or (b) eliminate the bulk of opposing nuclear forces in a surprise attack.
The US possessed it until the early 1970s, when the Soviet ICBM force was finally large and well-hidden enough (mostly through the invention of submarine missile carriers) to survive a first strike. The US feared the Soviets could do this at the beginning of the 1980s, and the Soviets also feared that US Gryphon/Pershing II missiles could do the same.
Russia and China have their ICBM forces ready to go in 15 minutes (fueled, but not targeted) and can detect an attack 10 minutes before first impacts, so both have it against each other. Russia and the US also require 15 minutes to launch but have 25 minutes' warning for an attack from one another, so neither have it there. The US and China don't have it with each other either.
The ability for nuclear forces to survive a full-scale nuclear attack and be able to launch a devastating counter-attack. In practice for the Americans and Soviets, this involves SSBNs and backup command centres, as well as having very large stockpiles of nuclear weapons. Standard thinking was that in a worst-case out-of-left-field all-out nuclear first-strike, 90% of one's stockpile might be lost. If your 10% that survive was numericaly big enough to annihilate your would-be attacker, that might be enough to dissuade the other side from striking first. This concept would become known as Mutually Assured Destruction.
This is the basis of why American and Soviet nuclear stockpiles were as large as they were during the Cold War. On the American side, war planners in the 1960s estimated that there were about 300 potential targets in the Soviet Union (arriving at that number by adding up all the industrial centers, military targets, and cities with at least 100,000 residents). Nuclear strikes at the time weren't guaranteed to be accurate; missiles could land as many as twenty miles off-target, or bombers might miss because of navigation errors, poor visibility, or being chased by enemy anti-air. Planners compensated by stacking three nukes per potential target. A rough calculation gets you to 9,000 nukesnote for Mutually Assured Destruction — at a minimum. Given the weirdness of Cold War politics, actual American and Soviet stockpiles topped out at 32,000 and 45,000 respectively.
Other nations, like Britain and France, had neither the money nor the warheads to maintain an arsenal like that, and their relative proximity to the Soviet Union meant they also didn't have the time to confirm an attack and launch a counter-attack. As such, they developed other means to secure second-strike capability, such as submarine-launched platforms and other command-and-control schemes (see below sections).
It takes about half an hour for a missile to go from the US to western Russia. It's only 10 minutes from Western Europe to Russia, 15 from western Russia to China, and even less than that from Soviet Asia. This is a factor in determining what sort of controls you would implement on your nuclear stockpile (see the UK's entry).
These two terms refer to what you're targeting, with "counterforce" targeting your enemy's nuclear weapons (airbases, missile silos, etc.) and "countervalue" targeting what your enemy would, well, value (cities, industrial centers, national capitals, etc.) This can affect the kind of nuclear attack you might make. If you're doing a countervalue strategy, your warheads would detonate in the air in order to spread catastrophe (shockwave, heat, radioactive material, EMP) over the widest possible area. Hardened military installations can survive that sort of attack, so for a counterforce strategy, your warheads will be designed to detonate on the ground. Ironically, given the location of the US's ICBM fields and the direction of the prevailing winds, a Soviet counterforce strike would have killed more American civilians than a countervalue strike due to major population centers being downwind of the strike.
The United States — Keep the Toilet Handy
The main worry for the United States was the survivability of its nuclear forces. Pentagon planners feared a Soviet first strike would cripple their nuclear capability and leave them defenceless. It was important to make sure that forces got off the ground as soon as possible.
The first example of this, before the ICBM and boomer fleet were fully operational, was the "aerial patrol" approach. Some American bombers would be in the sky 24 hours a day, in case of a sudden attack. They were under a system called "positive control" — bombers could not proceed beyond a certain point without a verified order from the President.
This had problems, namely nuclear bombs flying around. After a couple of "Broken Arrow" incidents, with resultant radioactive mess, this idea was abandoned. It also had the effect of keeping Soviet leadership in a constant state of terror because they saw nuclear-armed American bombers flying toward them 24/7. In this state of mind the USSR shot down a large South Korean passenger airliner (which had strayed over Russian territory), on the chance it might be an American trick.
The Strategic Air Command (SAC) then moved onto a strip alert system. It was initially thought that there would be an hour's warning before Mnogo Nukes started landing on many targets, but as the Soviet ICBM force got more capable, this was dropped to 15 minutes. As a result, SAC bomber crews (mostly in B-52s) would be kept on constant alert, ready at a moment's notice to rush to their aircraft and take off. SAC also contributed to the trope Offer Void In Nebraska — they had so much phone capacity to their main air base in Omaha that they gave the capacity to 800 services when not in use.
The United Kingdom — A Bloody Union Jack On Top Of It
British nuclear strategy was largely to coordinate with the US, but it had several differences informed by two major considerations. The first was the aforementioned lack of time; with possibly less than five minutes elapsing between recieving confirmation of a launch and the first mushroom clouds, it was accepted fact that the government would be wiped out before it could give launch orders. Royal Navy boomers therefore operated on a limited fail-deadly system; if they were unable to detect any of several signs of life from the UK, including Admiralty broadcasts and the Today program, the Captain was to open a set of sealed orders called the Letters of Last Resort and carry them out. This could mean anything from a full retaliatory strike to taking orders from Australia, depending on what the current Prime Minister decided when he or she wrote them. The letters are destroyed unread when the PM changes. Even today, Royal Navy Trident missiles don't need unlock codes transmitted from higher command to arm them.note
The second factor was that the British, not being the United States, couldn't afford as much in the way of armaments, being heavily in debt (primarily to the US) after World War II. Mutually Assured Destruction was just too expensive and unviable for the UK. It wanted just enough on the off chance that it still wasn't worthwhile for the Soviets. Also, the UK was worried that the US would think it was expendable and not defend it from a Soviet strike (and thus not risk being attacked themselves); as such, the British needed their own nuclear deterrent.
The British coined the term "Moscow criterion" for the ability to guarantee Moscow's destruction. But this wasn't easy. With only four Resolution-class submarines to launch them from sea (so not counting air-launched weapons), the UK had a total of only 64 Polaris missiles and 192 warheads. Even in the best-case scenario (i.e. assuming they're all still there and work properly), these were MRVs and not MIRVs, the difference being that although they'd be evenly distributed around the target and do more damage, they couldn't be independently targeted. Even the very limited ABM system around Moscow that the Soviets were allowed under the ABM Treaty (100 interceptors) was worrisome.
So the British designed an upgrade to their Polaris missiles; the Polaris A3TK, which was fitted with the Chevaline system. It reduced the number of warheads from three to two and cut range substantially, but it vastly improved the chances of those warheads to make it past Soviet defenses. Basically, the SLBMs would toss off a bunch of countermeasures and "penetration aids," and the Soviets would see a lot of fake, although realistic-looking, contacts with their various sensors, which would more than make up for the reduced number of warheads. The destruction of Moscow could be assured, and "peace and harmony" might prevail.
Due to the limited range of Polaris and the fact that Moscow is considerably further from a coast than London or Washington, British bombers would be up near the Barents Sea or in the Eastern Mediterranean. This explains why HMS Ranger is all the way
oop north up north when it's grabbed in The Spy Who Loved Me.
Compare with Ultimate Defence of the Realm.
The USSR — Bastion Areas
The Soviet Union's targeting strategy was "counter-value", namely focusing on economic targets and cities. Contrary to many perceptions at the time, the Soviets showed no interest in launching a first strike; they focused on surviving a first one (or disrupting preparations for a strike on them) with enough forces to launch a devastating counter-strike. They hardened their ICBM silos in the late 1970s and early 1980s; before then, they achieved this by deploying missiles in Cuba in 1962, within easy reach of the continental US, which led to the Cuban Missile Crisis.
The Soviet boomers had two differences to NATO ones. One, they were noisier. Two, after the arrival of the "Delta" class, they had considerably more range. This meant that some Soviet submarines could, if need be, launch their missiles from the dock and hit the US.
Since there was no point running the gauntlet of NATO naval forces, later Soviet boomers would stay in bastion areas near the Soviet coast. There, they would be protected by other subs and surface ships.
There was still a place for the older stuff though, such as the "Yankee" class. Due to the shorter time of missile flight, they would have been used to destroy time-sensitive targets in a nuclear war (namely bomber bases, boomers in port, etc.), if they'd been able to launch.
The "Typhoon" class can spend up to a year submerged, though in practice Soviet SSBNs in general stayed out for far shorter periods of time, due to political concerns about crew reliability; they would have been useful in launching a very late counter-strike.
The Dead Hand
Seriously worried (more than the West realised at the time) about the US launching a surprise decapitation attack in the early 1980s, with Trident SLBMs, Gryphon cruise missiles and Pershing II MRBMs, the USSR developed a system called "Perimetr". This semi-automatic system, which is believed to still be in operation, would delegate control of Russian missile forces to a senior commander if contact was lost with Moscow. Because the Perimetr is understandably above top secret, it's not precisely known what exactly it does. According to some sources, it gives ordinary officers rights to launch nukes without the president's permission; according to others, it automatically detects if the high command in Moscow no longer exists and automatically launches all nukes in that case.
There is some evidence to suggest that the reason that Perimetr was established was to help calm hotheads in the Kremlin, who, after a tense 1983, were seeing US first strikes everywhere.
The People's Republic of China — Minimal Deterrence
From its final conquest of China in 1950 to its production of a handful of nuclear-tipped missiles capable of hitting Moscow in the early 1970s, the Chinese Communist Party lived in constant fear of nuclear attack. Even before the Sino-Soviet Split and Border Wars of 1960 and 1969, Khruschev had promised to use the Soviet Union's nuclear arsenal against the US “only in the event that the United States uses large yield nuclear weapons, and in this way risks widening the war.” That meant that if the US looked like it was only going to bomb China, China was on its own. Obviously this was far from reassuring, so the CCP made its first formal request for help establishing a joint nuclear programme in 1957.
The Soviets thought otherwise. They withdrew all nuclear aid in 1959, reneging on a secret agreement made by Khruschev to supply the PRC with the blueprints of nuclear weapons and a few choice samples. The Soviets went on to withdraw all technical aid to Mainland China in 1960, including aid to the PRC's ballistic missile programme. During the Sino-Soviet Border War of 1969, the Soviets even explicitly threatened to launch nuclear attacks on the PRC's atomic energy sites if they refused to back down and agree to the Soviets' peace terms, which they did.
With the development of a nuclear arsenal, however, the CCP was faced with the question of how big it should be and what purpose it should serve. Drawing conclusions from Franco-British nuclear doctrine, they soon settled on an explicit policy of "limited" or "minimal" deterrence. As far as the CCP was concerned, any potential loss of life was enough to deter attacking it. This suited the PRC's needs very well. The PRC would never execute a first strike, especially considering that it was still quite poor and couldn't maintain the arsenal needed to do that. The PRC's nuclear arsenal remained at about half the size of Britain's throughout the war, and there are no indications it has grown past that size — though there are hopes that, with the development of better submarine technology, submarine-launched missiles could replace the PRC's land-based arsenal.
The PRC's management of its nuclear weapons generally focused on maintaining second-strike capability through the use of hundreds of dummy and hidden silos. This was necessary because Mainland China had only a tiny and primitive submarine industry to build on (Soviet help being terminated very early into the submarine corps' development), meaning that China's first experimental nuclear ballistic missile submarine wasn't launched until the late 1980s.
Israel is a nuclear power, albeit not officially, and it's been an Open Secret since the late 1960s. Its official policy is of "nuclear ambiguity", neither confirming or denying that it's a nuclear power at all. The reasons for that are quite complicated, but the end result is that it's much harder to figure out what its arsenal really consists of.
Israel had at least some warheads going back to 1968. It developed its nuclear program with French aid (which may have been mutual, with engineering assistance going the other way) and a large quantity of fissile material. The latter, depending on whom you ask, was either stolen from the United States, provided by them under the table, or provided by South Africa (a fellow "pariah state" during The Apartheid Era) in exchange for help enriching the raw uranium into weapons-grade material. The UK may also have been involved (according to credible newspaper reports around 2006-07), supplying essential hardware like heavy water to the program. (In a twist reminiscent of Yes, Minister, the export decisions appear to have been made by senior civil servants without consulting their cabinet ministers.)
The nuclear weapons came in handy in 1973, during the Yom Kippur War; the Israelis armed a number of F-4s with nuclear bombs and kept them ready on the ground. The US wanted to keep the Israelis from having to use their nuclear weapons at all costs, so they bailed out their ally in Operation Nickel Grass, a massive airlift to resupply the Israeli armed forces, which had gone through a good deal of their deadly paraphernalia in the fighting.
Today, Israel almost certainly has boosted-fission devices, and probably even a few thermonuclear warheads, too. It has developed nuclear artillery shells and may have even devised suitcase nukes.
France — Le Champignon Atomique
France was an early adopter, being one of the five declared nuclear weapons states under the 1968 Nuclear Non-Proliferation Treaty. It did so for several reasons, including national pride and a perceived need to be able to independently deter the Soviets. The French were rather afraid of the Soviets overrunning Western Europe, for obvious reasons, not least of which that they'd only just got done throwing out les Boches. France faced the same problem as Britain in that it couldn't build enough warheads and delivery systems to totally wipe out the USSR, so it decided to build just enough to deter the Soviets. As Charles de Gaulle put it: "Within ten years, we shall have the means to kill 80 million Russians. I truly believe that one does not light-heartedly attack people who are able to kill 80 million Russians, even if one can kill 800 million French, that is if there were 800 million French."
Initially, the French nuclear deterrent was based on nuclear gravity bombs, carried by Dassault Mirage IV bombers. At first, they were intended to go in at high speed and high altitude, but feasibility issues forced them to be modified for low-altitude penetration with stand-off weapons. France also developed a variety of tactical nuclear weapons, including tactical nuclear gravity bombs and some nuclear artillery systems (intended as a warning to incoming Soviets), and was one of the first countries to develop its own version of an "enhanced radiation warhead", otherwise known as a Neutron Bomb. Today, the French strategic nuclear deterrent is mostly submarine-based; they commissioned their first boomers in 1971, and have been modernizing and replacing their force since then.
Early in 2008, France announced that it would cut its nuclear arsenal to 200 warheads, half of what it is authorized. France doesn't really have enemies in the Middle East (the only countries that might have a reason to do something), none of those countries can reach France by missile anyway, and the only countries strong enough to invade France — i.e. the US and Russia — don't have a problem with France anyway.
India — By All Means at Her Disposal
India's possession of a nuclear arsenal is a mystery — assuming one wasn't aware of the first 30 years of Indian independence, upon which it becomes a lot less of a mystery. Even before independence, Indian physicists considered the applications of atomic weapons at recently-founded centers like the Institute of Fundamental Research. The specter of war with its neighbor Pakistan loomed, but it was the 1962 Border War with China that fueled Indian interest.
The final push, however, is one rarely considered by western audiences: the appearance of nuclear-armed aircraft within the US Enterprise carrier group in the Bay of Bengal upon India's entry into the Bengal War of Independence in 1971. While it's frequently assumed India and America are always allies, regardless of seeing eye-to-eye, Indira Gandhi considered Richard Nixon more than a little unstable and predictable, America was Pakistan's foremost international ally, and more than a few political figures and pundits demanded a formal American action against India in 1971. Common sense demanded attention be paid to the dozens of nuclear weapons sitting in fully-fueled aircraft right off the coast. India's nuclear policy was born out of that turbulent time. Accordingly, it followed the lead of one of its allies, the USSR, and took it a step forward by formally announcing a "no first use" position based on a criteria of "minimum deterrence".
Pakistan — Leave us alone or else
When India became a nuclear power, Pakistan began its own programme in response. When the Soviets invaded Afghanistan and placed 600 tanks on the Pakistani border, it became a necessity. Unlike, India, Pakistan has a fairly straightforward posture: "minimum credible deterrence". It means that if the Soviets and or Indians threaten Pakistan with annihilation, Pakistan has the ability to guarantee destruction on an unacceptable scale, and Pakistan will maintain an arsenal at the minimum size necessary to achieve such objectives. Soviet and Indian population centers are near the Pakistani border (from a few tens to a few thousands of kilometers) so Pakistan has for now eschewed ICBMs in favour of air launched cruise missiles, aircraft, and mobile IRBMs. In a war, their jobs will be to ensure that dozens of enemy cities suddenly are in need of urgent urban renewal.
Then there's Pakistan's "strategic ambiguity". While the purpose and scope of Pakistan's arsenal is clear, the circumstances requiring its use are very much not. Pakistan has not defined the "minimum" size and composition of its arsenal, nor has it exactly defined what it deems to be a threshold which triggers its use. Pakistani leaders' stonewalling on the subject makes Israel look like a model of openness. This ambiguity seems to be to ensure that enemies will be more cautious in dealing with Pakistan. With the end of the Cold War, Russia is no longer a threat since the Central Asian countries are pro-Russian and contain few easily-digested concentrations of mistreated minorities on the other side of their mutual borders who are sitting on important strategic assets or resources. Pakistan's primary focus now is India, but some suspect contingencies exist for Israel or Iran.