Having covered the practicalities of nuclear physics, nuclear weapon design, and nuclear weapon effects, we may now turn our attention to the strategies that have grown out of these physical realities.
7.1 Tactical and Strategic Weapons
Broadly speaking, there are two kinds of nuclear weapons – tactical and strategic. This post has been focused primarily on strategic nuclear weapons, high yield weapons capable of destroying cities and hardened targets. Tactical nuclear weapons have smaller yields, allowing them to be hypothetically used on a battlefield that contains friendlies.
The line between the two gets somewhat blurred with the highest yield tactical weapons. Is a 5kt bomb tactical or strategic? No one really has a clear answer. These already crystal clear waters get muddied further when you add in “dial-a-yield” weapons, which can yield anywhere from <1kt to ~100kt. On the low end, they’re definitely tactical. But at the high end, they’re clearly strategic.
Most of the treaties that deal with nuclear weapons don’t cover tactical weapons. This is a bit of a problem, because tactical weapons are perhaps the easiest way that a conventional conflict could escalate into a nuclear conflict. It goes like this: my army is losing, so I have a fire-team use a tactical nuke launched from a recoilless rifle on your densest concertation of tanks. The 100t weapon totally destroys the formation, swinging the battle in my favour.
The nuke I used on you, the opposing general, is not a strategic weapon, so I don’t need codes from higher up or another person to agree with my decision.
You are now losing because those tanks occupied a key position. You reply with a 1kt tactical nuke of your own, fired from an 8” howitzer 20km behind your own lines. It takes out 3,000 of my infantry. Satisfied, you go back to conventional war.
But I’m pissed off, so I dial up one of my short ranged tactical missiles to a 10kt yield. There’s a plume of smoke from the rocket launch, a bright flash, and a crater where your army used to be. I’m satisfied with a job well done, but your side is pretty enraged. So they call in a 50kt strategic nuke on an intermediate range ballistic missile that wipes out my forces and camp.
A few more levels of escalation and the ICBMs and SLBMs begin to fly. Once you believe nuclear war is inevitable, the only thing to do is try for a successful first strike and pray for the best.
7.2 First Strike, Second Strike, Counterforce, Countervalue
A first strike is an attempt to destroy an opponent’s nuclear arsenal before they can launch it at you. SLBMs or on station stealth bombers are the only real way to pull this off. The flight time for ICBMs between probable belligerents is much too long for the missiles to reach targets before those targets have a chance to respond.
Targets include airbases where nuclear bombers are known to be based, the known location of any mobile ICBMs, missile silos, docks where nuclear submarines may be resupplying, command and control systems, and key nuclear weapons decision makers. Separately, any nuclear submarines that have be detected will be attacked by the hunter-killer submarines shadowing them.
In all likely nuclear exchanges between larger nuclear powers (NATO/Russia, NATO/China, China/Russia, China/Pakistan, China/India, India/Pakistan, Pakistan/Israel and neglecting North Korea due to the primitive nature of its nuclear program), this won’t be enough. Some of the nuclear weapons will survive.
Baring a truly unlikely display of self-sacrifice and forgiveness, these remaining weapons will immediately be fired at the aggressor in a second strike – a retaliatory attack.
First strikes are predicted to be mostly counterforce, that is to say, aimed at an enemy’s military forces in general and their nuclear forces in particular. There will be civilian casualties, because there always are, especially with weapons as indiscriminate as nukes, but civilian casualties aren’t the goal of a first strike.
A second strike, on the other hand, would be primarily countervalue, that is to say, aimed at the most valuable targets an enemy possesses. Major cities, knowledge centres, and industrial centres are the primary targets in a countervalue strike. Civilian casualties are kind of the point and consequently will be rather high.
7.3 Mutually Assured Destruction
Nuclear policy has for decades been based on the idea of mutually assured destruction (MAD). Mutually assured destruction requires all nuclear armed powers to be committed to a massive countervalue retaliatory strike against any country which deploys nuclear weapons against them. Furthermore, this threat must be credible – enemy decision makers must believe it is real and can be carried out if necessary.
The goal of the mutually assured destruction doctrine is to prevent nuclear war by making it clear that all nuclear wars will be unwinnable, so that no power believes they can gain anything from them. Wargame succinctly summed up the desired end-state of the MAD doctrine with the famous line “the only winning move is not to play”.
For MAD to ensure stability, two things must be true:
- No actor can destroy the entire nuclear arsenal of another in a first strike.
- No actor can defend against a second strike well enough that they will escape unscathed.
While the current MAD equilibrium is relatively stable, it has come under threat from both the US and the USSR in the past. The closest we’ve come to nuclear self-annihilation has been those times when MAD had begun to break down.
The Cuban Missile Crisis was ultimately about first strike capability. The US had based ballistic missiles in Italy and Turkey that gave it the easy ability to target the USSR – and Soviet missiles (of which there were only 20 that could hit the continental United States from Soviet territory). With these forward deployed missiles and timely reconnaissance from the U2 spy plane, it had become perhaps possible for the US to wipe out the Soviet Union and face minimal retaliation.
When the Soviets began to build missile sites in Cuba, the problem became mutual. Suddenly each side had first strike capability. If you want to look for the hand of God in human affairs, I would suggest centring your search here. Conditions were riper for a first shot than a Mos Eisley cantina. It’s a genuine miracle that no one launched missiles.
The negotiated resolution to the Cuban Missile Crisis was publically all about Cuba. Kennedy promised to never invade again and Khrushchev promised to remove the missiles. But in secret, Kennedy promised to remove all of the US missiles based in Italy and Turkey. First strike capability was removed and equilibrium restored.
The second threat to MAD came from anti-ballistic missiles (ABMs). By the 1960s, both the US and USSR were working on ABM systems. The Soviets were building a network of ABMs around their capital Moscow, while the Americans were building a similar system around their missile silos in North Dakota.
These systems were imperfect and could be overwhelmed by MIRVs. But both sides were worried about the future; what if their enemy figured out perfect missile defense before they did? Both the US and USSR knew that If one side could gain a critical advantage in missile defense, they would be able to launch a first strike with impunity. The bitter irony was that systems designed to protect against nuclear attacks were making global nuclear war more likely.
This crisis was also defused through diplomacy. Both sides understood the risks and decided they weren’t worth it. The first Strategic Arms Limitation Treaty (SALT I) limited both the USSR and US to two ABM sites. Hot on the heels of this was the Anti-Ballistic Missile Treaty which revised the limit downwards to one site and limited the number of ABMs at each site to 100.
Unfortunately, the US unilaterally withdrew from this treaty in 2002 to begin work on a new missile defense system. If this system ever becomes operational to the point that the US can expect to survive a second strike from Russia or China, nuclear war will become imminent.
7.4 The Nuclear Triad
The delicate balance of MAD is maintained by the nuclear triad: ICBMs, SLMBs, and conventional bombers. Once a nation possesses all three legs of the triad it becomes almost impossible to remove their nuclear capability in a first strike.
Each leg of the triad has a purpose. ICBMs are static, but are relatively cheap and can often be launched quickly. SLBMs are more expensive and slightly harder to launch (they require accurate positioning for targeting) but are very hard to destroy. And conventional bombers have the greatest flexibility in avoiding attack, plus a very long range courtesy of in-air refueling.
These aren’t the only three methods that can round out a triad though. Really, the important thing is having three credible and disparate systems, such that it is impossible to remove your ability to make a countervalue second strike. Space based weapons (forbidden by treaties), air launched missiles, carrier based nuclear bombers, or nuclear torpedoes could all be used in place of one of the “standard” legs of the triad.
Only India, China, the United States, and Russia have confirmed nuclear triad capability. Israel is suspected of having a nuclear triad, but refuses to confirm or deny this assertion (Israel does wink suggestively when asked, which has led basically all experts to assume that they do in fact possess a nuclear triad).
7.5 Current Nuclear Strategy
Every country charts its own course on nuclear weapons. From public statements and acknowledged procurements, it’s possible to get some idea of each country’s strategy, but you have to understand that they really don’t broadcast these things. I mean, they broadcast them, but we shouldn’t take those statements at face value. There are a host of reasons – diplomatic, strategic, domestic, that prevent leaders from being entirely candid with their nuclear plans.
When reading into strategies, I focus on questions like: what are the known capabilities of deployed weapons? How many nuclear weapons can a country deploy? What delivery methods does a country possess? Where are its weapons based? What advances in technology are politicians highlighting in public speeches? Where have they faced technical difficulties? What countries are they friendly with? Unfriendly with?
I would also recommend avoiding the common pitfall of obsessing over the total number of warheads a country possesses. This number is much less important than the count of operational or deployed warheads. In any significant nuclear exchange, it is unlikely that any warheads but those immediately at hand for deployment will be used.
This section represents my best guesses at the current nuclear strategies of various countries. Please treat these as speculation, not as fact.
Russia wants to keep its status as a major nuclear power, but it needs to do it on a tighter budget than the USSR had. This means a focus on land based ICBMs, no truly stealthy fighters, and limited resources for its SLBM program.
Current sanctions on Russia have disrupted Russian supply chains and applied pressure on Putin to slash military spending – right as he becomes more confrontational with the rest of the world. Russia can’t afford to fall behind in the nuclear arms race. Its second strike capability is the only thing stopping the US from giving it much harsher ultimatums. Significant budget cuts would put this second strike capability under threat. But on the other hand, Russia can only afford its current military budget for so long.
This statement falsified if: real stealth bombers enter service with a sticker price of >$500,000,000 per unit, Russia manages a string of successful SLBM launches in 2017, the international sanction regime against Russia collapses with Trump as US president.
China’s nuclear arsenal is less advanced than that of Russia or the USA. MIRV-ready missiles have been rolled out only in the last decade and many of their missiles still lack MIRV capability (but they do incorporate some decoys and countermeasures). In addition, Chinese missiles are kept unfueled and without warheads in place, which drastically increases their second strike response time. They make up for this with a massive network of decoy silos, real silos, and tunnels built into the mountains of Central China. China only has a handful of nuclear missile submarines and its conventional bomber force is fairly obsolete.
China’s nuclear policy is explicitly second strike only. Based on all the facts above and what I know about China, I’m inclined to believe this. Historically, China has never cared much about what happens outside of China (broadly defined, of course). Since China already enjoys massive conventional supremacy over its neighbours, it has no need of nuclear weapons to intimidate them.
This statement falsified if: China renounces no first use, China threatens a non-nuclear state with nuclear attack, China has >10 active ballistic missile submarines by 2020, China develops a new dedicated heavy bomber.
7.5.3 India and Pakistan
Neither of these countries have sprung for forces really capable of mutually assured destruction and only India maintains a full nuclear triad. Instead of adopting MAD, they instead both aim to have forces just big enough to make a nuclear attack by the other not worth the risk.
Since these countries really only need to be able to deter each other (and possibly China), they’re freed from the need to spend to keep up with the US or Russia. Both India and Pakistan lack the ability to launch a truly significant countervalue strike in response to a first strike from the US or Russia. Given how unlikely the US or Russia launching a first strike on India or Pakistan is, this is a sensible approach.
This statement falsified if: Either of these countries test Mt range thermonuclear weapons, either of these countries develops an ICBM capable of targeting the continental United States (range >11,000km), either of these countries increases nuclear funding by >200%.
7.5.4 UK and France
These countries keep nuclear weapons because they’re members of the UN Security Council and it comes with the territory. Neither has a particularly robust nuclear force (the UK only has American made Trident SLBMs, France has indigenous SLBMs and nuclear capable bombers). It’s largely a prestige thing though. Neither country has been particularly enthusiastic about the nuclear rigmarole (and its price tag) since the end of the Cold War.
Nuclear policy in the UK and France is closely tied to the nuclear policy of NATO, although both countries do maintain some ability to conduct nuclear war on their own terms. Neither country has ruled out using nuclear against non-nuclear states in response to attacks with conventional forces and France has specifically mentioned that they would be willing to use nuclear weapons against countries that sponsor terrorism against them.
All this being said, it is unlikely that France or the UK would be the ones to start a global nuclear war.
This statement falsified if: Either the UK or France increases their supply of operational warheads, either the UK or France develops a full nuclear triad.
7.5.5 North Korea
North Korea’s nuclear weapons program is especially difficult to assess. In addition to the normal challenges when trying to understand a classified program, there’s the bluster of Kim Jong-un to sort through. Up until recently, experts thought ICBM technology was beyond North Korea. They were thought to be struggling with the re-entry heat shield, struggling with miniaturization, struggling with the whole endeavour.
Now, people are less sure. Has North Korea gained full ICBM capability? Or is this more bluster and staged photographs? There’s probably a dozen men and women in the Pentagon (and in many other places) who would love to know the answer for sure. My personal guess, based on the evidence (and the bluster) is that North Korea has a missile design that in theory could target the US, but they’ll need a year or three to get it working reliably. I don’t think they’ll pull off a successful test this year, but I won’t be surprised if they pull one off in 2018 or 2019. That also seems to be the view of the Ploughshares Fund, an anti-proliferation non-profit.
Even if North Korea can’t attack the US, there’s still Russia, China, Japan and South Korea at risk from its shorter range missiles. This represents a considerable threat to a large number of people. It’s tempting to laugh off these threats in light of the inflated numbers that North Korea likes to give for the yields of their weapons (e.g. claiming a 6kt detonation was a hydrogen bomb that could wipe out the whole US). You could look at the disconnect as evidence of a fizzle, but personally I see it as evidence that North Korea likes to exaggerate. In September, they tested a bomb with a yield of 10-20kt. Fizzle or not, if delivered to Seoul, it would kill over 100,000 people.
Under Kim Jong-il, the prevailing belief was that the nuclear program was a bargaining chip in order to get free food or other concessions from other countries. Its purpose under Kim Jong-un is less clear. Despite punishing sanctions, Jong-un has maintained and expanded the nuclear weapon and missile programs started by his father. Whether he is willing to trade them in for concessions or wishes to use them in an attempt at unification is unknown.
This statement falsified if: North Korea successfully tests a true ICBM (range >5,500km) with successfully atmospheric re-entry by the end of 2017 and analysts believe it has enough additional payload for a miniaturized bomb.
Israel’s nuclear weapons remain unacknowledged, because Israel has pledged to not be the country that “introduces” nuclear weapons to the Middle East. Israel’s statement should be given all of the skepticism one would give to Bill Clinton using the word “is”. Israel may intend “introduce” to mean “acknowledge” or “deploy”, but we’re all pretty sure they don’t intend “introduce” to mean what it literally does.
Israel wants to have nuclear weapons as the ultimate hedge against military aggression by its neighbours. In addition, it wants to ensure that none of its neighbours possess them. Given the clear support for genocide that some of its neighbours have expressed, this position is understandable. If it appears likely that one of its regional foes will develop nuclear weapons, Israel is likely to launch a conventional attack to stop their development. If a conventional attack fails, a nuclear one is not out of the question.
Many sources talk about how Israel holds nuclear weapons as a “Samson option” and is prepared to use them to utterly annihilate an enemy if it looks like they are in a position to destroy Israel. This is actually how I’d expect most countries to behave, so I think the obsession with the Samson Option in Western reports on Israel’s nuclear program has more to do with the story it makes than a real difference between, say, France and Israel.
Israel probably possesses a full nuclear triad. Since it does not confirm or deny its nuclear program, there are no publically available official details that would allow us to be sure of this. It does make sense though. Israel has the technical know-how to pull off the tricky parts of a triad, like SLBMs.
In the future, we can expect Israel to continue to hold onto its arsenal and continue to neither confirm nor deny its existence. I don’t think Israel is a particularly likely candidate to touch off a nuclear war, as it is unlikely to use nuclear weapons against another nuclear armed state. That said, Israeli use of nuclear weapons would almost assuredly result in many civilian casualties and is still an eventuality that basically everyone would like to avoid.
This statement falsified if: Israel joins the NPT and allows inspectors into its nuclear facilities, Israel publically acknowledges its nuclear arsenal, Israel does not launch an airstrike against any nuclear program started by another Middle Eastern country.
Iran does not possess nuclear weapons, but as recently as 14 years ago was probably working on them. Most analysts believe that this work mostly stopped with the US invasion of Iraq. Iran had no particular desire to become (more of) an international pariah for developing nuclear weapons, but couldn’t accept the risk of Iraq developing them without an Iranian counter. Iran remembered the nerve agent attacks that Iraq unleashed (with the assistance of the US) during the Iran-Iraq war and felt that any developments in Iraqi weapons of mass destruction had to matched.
Iran has been prevented from coming clean about its past development of nuclear weapons by the belief (rightly or wrongly) than any admission will result in sanctions or attempts at regime change from Western actors.
Iran does have a well-developed civilian nuclear program. Despite the wailing and gnashing of teeth among hawks, the current nuclear deal should prevent any breakout towards nuclear weapons. The deal includes a robust enforcement and inspection regime that has most global powers convinced that Iran won’t be able to restart nuclear weapons work secretly.
Donald Trump’s talk of reversing this deal is just that: talk. It isn’t a bilateral deal between Iran and the USA, it’s a multilateral deal between Iran, the Permanent members of the UN Security Council, and Germany. The US could unilaterally re-impose sanctions, but there would be a significant diplomatic cost for basically no gain; it took a network of international sanctions to bring Iran to the negotiating table the first time around, so it is doubtful that US sanctions alone would change anything. The Iranian economy isn’t very integrated with the US economy, further diminishing the sting of any unilateral sanctions. Honestly, the US would probably suffer just as much from a fresh round of sanctions as Iran would.
This statement falsified if: Iran renounces the nuclear deal, Iran leaves the NPT, Iran refuses to allow inspectors access to a site they wish to visit, inspections turn up clear evidence of nuclear weapons development done since 2005.
7.5.8 The United States of America
When Vladimir Putin goes to his magic mirror and asks “mirror, mirror on the wall, who’s the greatest nuclear power of all?”, the answer is invariably “the United States”. In every nuclear metric that matters (so, discounting the total number of warheads), the United States reigns supreme. It has the best stealth bombers, the most accurate missiles, and the biggest fleet of nuclear submarines. As the world’s one remaining superpower, the United States is the only country that is able to mount even a half-way decent first strike – although it probably can’t launch a successful first strike against any triad state.
I don’t know what US nuclear policy will look like going forward. If Donald Trump maintains good relations with Putin, then a nuclear exchange with Russia will be (even more) unlikely. I do think a nuclear exchange with China has become slightly more likely as a result of Donald Trump’s election, but I hope the risk is relatively low.
No matter how you cut it, the risk of a nuclear exchange is – and always has been – low. But no one truly knows how low “low” is. Is it 10% over the Trump presidency? 1%? Whatever it is, I wish it was lower.
I also wish Trump was less of a loose cannon. I can’t really make predictions about America’s nuclear policy over the next few years because the information I have is too heavily weighted towards hyperbole and bluster.