The Risk of Nuclear War Between India and Pakistan

Nuño Sempere, Vidur Kapur, and Lisa discuss the possibility of nuclear escalation between India and Pakistan.

Timestamps

(00:16:00) - Intro

(00:43:00) - Background on the conflict

(02:26:13) - Direct forecasts of nuclear weapons use

(15:45:10) - The role of other nations

(20:26:09) - What if Pakistan collapses?

(22:45:16) - Russia's incentives in global conflicts

(25:40:08) - What are the forecasters looking out for next?

(29:28:06) - Outro

Transcript

The transcript is AI-generated and slightly differs from the phrasing used in the recording.

Rai Sur

00:00:16

Welcome to the Sentinel podcast, where top forecasters discuss ongoing events with a view towards better understanding global catastrophic risk. Today, we'll be talking about the recent military escalation between two nuclear weapons states, India and Pakistan. I'm your host, Rai, and I'm joined by three of Sentinel's world-class forecasters: Nuño Sempere, who's also my co-founder at Sentinel; Lisa, also known by her forecasting moniker, Be Like Water; and Vidur Kapur. The situation is evolving rapidly, and we are recording this on Wednesday, May 7th.

To ground the discussion, the focus will be on nuclear risk, as Sentinel is concerned with escalations in the long tail of extremely bad outcomes. Most of that risk here is nuclear.

About two weeks ago, a terrorist attack in Jammu and Kashmir, a contested territory on the India-Pakistan border, killed 27 people (mostly Hindus) and injured 20 others. This caused an immediate diplomatic breakdown that has since escalated to military action at a scale not seen since the last Indo-Pakistani war in 1999.

India's nuclear program conducted its first nuclear test in 1974, and Pakistan had theirs in 1998, but neither has tested a weapon since 1998. The countries have very different nuclear doctrines. India committed to a no-first-use doctrine in 1998, meaning they pledged not to use nuclear weapons proactively. Pakistan, however, affirmed as recently as this conflict that it expressly does not have a no-first-use doctrine. With a significantly weaker conventional military, Pakistan uses the threat of nuclear first use as a deterrent.

Regarding their nuclear arsenals: India and Pakistan both possess numerous warheads and missiles capable of covering each other's entire territories. As of 2013, Pakistan stated it would need to assemble a nuclear-armed missile from parts stored in different locations, though it's unclear if this remains true. India has new missiles that can be permanently mated with warheads and stored ready for use. It's unclear if any of these missiles are currently mated to nuclear warheads.

With that background established, I'm curious where you all are starting on this question. What's your rough estimate of the probability of at least one nuclear weapon being launched by either India or Pakistan in the next 365 days? How are you arriving at that, and what are you considering? Let's start with Nuno.

Nuño Sempere

00:02:44

Before this recent escalation, I was at approximately 0.1%. I arrived at that by decomposing the question into: first, the chances of a significant escalation, and second, conditional on that escalation, the chances of a nuke being used.

In our forecast a week ago, we defined the threshold for significant escalation as 1,000 deaths. This is much higher than the 27 deaths seen so far. However, India's response seems more kinetic than I expected.

If I was previously at a 12% chance of significant escalation and a 1% chance of nuclear use conditional on that, my estimate for hitting that 1,000-death threshold might now be around 15% to 20%. This brings my overall estimate from 0.1% to perhaps 0.2%.

Overall, I believe it's still unlikely because both sides really don't want it. However, there's a dynamic where both sides are uncertain, capable of making mistakes, and could start on a path they cannot stop.

Rai Sur

00:03:58

Vidur, what about you?

Vidur Kapur

00:03:59

There are a few different ways to approach this question. One is, like Nuno, to take this in stages. You could look at the probability of a significant escalation—for example, 1,000 military fatalities within the next 12 months—and then, conditional on that, the probability of nuclear weapon use.

For me, I'm now at around 20% for 1,000 military fatalities within the next 12 months. Conditional on that, I'm at possibly around 2% to 3% for actual nuclear weapon use.

This puts me a fair bit higher than Nuno, at around 0.4% to 0.6% overall. Taking the average, I estimate a 0.5% chance of nuclear weapon use by either India or Pakistan within the next 12 months.

Rai Sur

00:05:11

It might be good to contextualize this second part: where the nuclear use percentages come from.

Vidur Kapur

00:05:16

Absolutely.

Rai Sur

00:05:17

There seems to be a range of numbers most forecasters coalesce around for nuclear weapon use. How do you arrive at those figures? What's their origin?

Vidur Kapur

00:05:29

The second part is to determine the base rate for nuclear weapons use in a conflict. In the past 80 years, coinciding with the 80th anniversary of the end of World War II, there has been essentially one instance of nuclear weapon use in conflict—the two bombs in Japan, which I count as one event. This gives a base rate of 1 in 80, or about 1.25%.

Looking closer, when the United States used nuclear weapons, it was the sole nuclear state. Japan couldn't retaliate as it lacked nuclear weapons, possessing only a crude program. The Soviet Union, Germany, and Britain also didn't have them at that time. This suggests the probability of nuclear use in the modern age is lower than 1.25% because states are hesitant to break the norm against their use.

In the India-Pakistan case, both have nuclear weapons, meaning mutual use would cause immense destruction on both sides. This might push the probability lower. However, Pakistan's military doctrines suggest a willingness to use nuclear weapons under certain circumstances. One scenario involves a battlefield commander using tactical nuclear weapons, which Pakistan possesses. Doctrines indicate a willingness to use them, especially against an existential threat to Pakistan.

One could also imagine a general, in the fog of war, deploying tactical nuclear weapons to halt an Indian advance. If India made an incursion, a general, perhaps misinformed about broader Indian gains, might panic and use them. This specific scenario is concerning and pushes my estimate higher than 1.25%.

Generally, the ongoing conflict itself suggests a higher probability. If India and Pakistan were at peace, nuclear use would be unlikely, barring an accident. But with an active conflict and reports of downed Indian jets, we should consider a rate higher than 1.25%, possibly 2% to 3%.

We also know that former Secretary of State Mike Pompeo stated in his memoir that during the 2019 India-Pakistan escalation, both countries were very close to using nuclear weapons. While he might have exaggerated for his memoir, it's another data point suggesting these countries are among those most liable to use nuclear weapons in a conflict scenario.

Nuño Sempere

00:09:25

Fedor, that 1.25% is for all countries collectively. What share of that risk do you assign specifically to India and Pakistan? Considering the large number of nuclear states, the base rate per year for a state *not* using nuclear weapons is quite high.

Conversely, there have been events close to nuclear weapon use. North Korea's nuclear tests to deter the US are an example. More recently, Russia's seizure of the Zaporizhzhia nuclear plant could also be considered, potentially expanding the reference class. What are your thoughts on this, especially regarding the share of the 1.25% attributable to India and Pakistan?

Vidur Kapur

00:10:22

My estimate of 0.4% to 0.6% implies a significant share for India and Pakistan. Much of the remaining risk, in my view, currently lies with Russia in Ukraine, as Russia has explicitly discussed using nuclear weapons. In autumn 2022, Western policymakers were very concerned about Russian nuclear use; the British Prime Minister was reportedly monitoring weather patterns due to fears of nuclear fallout. So, Russia and Ukraine account for a large share.

However, aside from these two, it's justifiable for India and Pakistan to represent a substantial portion of the nuclear risk within the next year, given their current conflict. As we speak, Indian pilots may be hospitalized due to downed fighter jets. Indian officials have briefed The New York Times and The Hindu that at least three fighter jets are down.

While they don't constitute the entire risk, they justifiably form a major part of the nuclear risk for the coming year.

Rai Sur

00:11:44

Lisa, what are your thoughts here?

Lisa

00:11:46

My forecast for nuclear weapon usage risk aligns closely with Nuno's, around 0.1% to 0.2%. I'll say 0.2% due to recent escalation. However, my overall view is that because both are nuclear powers, the risk of them ever using nuclear weapons is extremely low; the consequences are too high. An incredible escalation would be necessary before we'd see nuclear weapons used.

Consider Ukraine versus Russia: despite numerous threats of Russian nuclear use contingent on Ukrainian actions, it hasn't happened. No rational country wants to use nuclear weapons in almost any scenario. Therefore, the risk is extremely small.

Most of the current risk, in my opinion, stems from accidents or misunderstandings. For instance, if one country inaccurately perceived the other's actions, it might lead to a misjudgment and nuclear use. This is the most likely path to nuclear weapon use in this conflict.

Another factor is the significant imbalance in country size, military size, and military budgets. Pakistan spends $10 billion annually on defense, while India spends $81 billion. Due to this asymmetry and other reasons, neither side wants this conflict to escalate. They will likely try to de-escalate after responses that satisfy domestic political needs.

This is my framework: events have occurred, and each side must respond to some degree, but neither wants an uncontrolled escalation. I don't see a substantial risk of this escalating to actual nuclear war.

Vidur Kapur

00:14:18

A counterargument is that in the Russia-Ukraine scenario, while both sides really, really hate each other, Ukraine was held back. The United States supplied many of Ukraine's weapons and calibrated its support to avoid nuclear escalation. President Biden recently acknowledged in a BBC interview his deep concern about World War III and nuclear escalation, stating he didn't want to "play roulette."

With India and Pakistan, you have two sides that really hate each other, and emotions run high. Neither side wants nuclear escalation. However, if mistakes occur, or events deviate from plans, such as fighter jets being shot down, it creates an incentive to respond more forcefully.

While the chance of this leading to nuclear escalation is very small, if fighter jets are shot down, India might feel compelled to respond even more strongly. Pakistan already feels the need to respond to airstrikes on its territory. This could escalate because both sides feel the need to save face, perceiving themselves as losers in the scenario, and there's no one effectively holding them back.

The United States might intervene, but it is currently preoccupied with other crises like Gaza, Iran, and Ukraine. This creates a potential path toward nuclear escalation, driven by the need to save face and heightened emotions.

Lisa

00:16:19

Vidur, your point about the role of other powers is excellent. In the India-Pakistan case, no single power is directly restraining either country as we've seen with Russia-Ukraine.

However, another angle to consider is that other powers are implicitly backing India and Pakistan. If the India-Pakistan conflict escalated, we must wonder if it would draw in China, the US, and Russia. I believe these powers are already implicitly involved.

Rai Sur

00:17:07

Let's discuss other powers and the potential for de-escalation.

Vidhur, you mentioned the US might have its hands full. It's unclear to me how many foreign crises the US can manage simultaneously. You implied this might not be on their radar due to existing commitments. Given current US engagements, how involved do you think they are, and how much will they try to de-escalate this situation?

The same question applies to other countries: What are their interests, and how much attention are they paying?

Vidur Kapur

00:17:45

It's an interesting question how much a country can take on at once. In the US case, several factors are relevant. Sometimes, the same top personnel handle multiple conflicts, so a drive from top leadership to achieve resolution makes a significant difference in negotiations.

Disinterestedness could play a role. If top leaders, for instance, are too occupied with other priorities to focus on this, it might slip under the radar. However, you're right; the US government has many employees, and diplomats can often proceed without constant top-level direction. Still, central leadership matters in government.

I'm also curious about Lisa's points on Russia, China, and potential US involvement. I agree they are implicitly funding and selling arms to India and Pakistan.

Lisa

00:19:11

Exactly, they are already involved in a sense. If things escalated, I wonder if the United States would implicitly back India—though Pakistan has been an ally, albeit to a lesser extent—and if China, which sells arms to Pakistan, would implicitly back Pakistan.

As in all conflicts, there's a broader context and potential for wider involvement. All major powers, in addition to India and Pakistan, would prefer this conflict not to escalate. Nobody wants escalation.

Fundamentally, India and Pakistan don't want to solve this problem now. It's too large and won't be resolved overnight or through military tit-for-tat. This is a conflict that will likely continue and simmer for a long time, with occasional flare-ups. I foresee it continuing this way for many years.

Nuño Sempere

00:20:25

Beyond international dynamics, another factor is Pakistan's internal situation. The Pakistani state and military appear reasonably weak. The Kashmir conflict began, in part, because they couldn't effectively suppress rebels wanting to annex Indian Kashmir. Additionally, rebels in Balochistan are killing police and staging attacks.

Considering a scenario where the India-Pakistan conflict reaches 1,000 deaths, is my 1% probability of further escalation too low? Is there, perhaps, a 2% chance of Pakistan collapsing? If so, where are the nuclear weapons physically located? Are they in the capital or more spread out? Is there a chance a rebel group could acquire a nuclear weapon?

For example, Bangladesh seceded from Pakistan with India's help. Could something similar happen with Balochistan? I'm not certain about the distribution of nuclear weapons within Pakistan, but this uncertainty might be a reason to increase my conditional probabilities of escalation.

Lisa

00:21:45

To me, the overriding concern is the mutual assured destruction doctrine, which seems to supersede everything else.

Nuño Sempere

00:21:57

I agree with that overriding logic, but it assumes the current Pakistani state is in control. If I'm considering 1% or 2% probability scenarios, I might need to condition on that assumption being incorrect.

The Pakistani military opposed Imran Khan, who was popular. Could protests arise, combining various dissatisfied groups? If I consider the chances of the Pakistani government falling within a year, does that probability reach 1%? I'm honestly not sure.

Lisa

00:22:33

In a sense, what you're describing is the risk of nuclear proliferation. There's a non-zero risk associated with that concern.

Nuño Sempere

00:22:44

Another factor on the international stage is that the US and China don't want to see nuclear weapons used. However, Russia's calculus is a bit more complicated. Russia, to some extent, benefits from chaos, particularly if it captures some US attention. It is also more integrated with North Korea and Iran.

It would also benefit from a war involving Israel, as this would divert US attention from the front in Ukraine. If the US were decisively on Pakistan's side, Russia might benefit from supporting India, creating another front. What are your thoughts on that?

Lisa

00:23:28

I completely agree that Russia likes to sow chaos everywhere. The more chaos there is, and the more other powers are occupied dealing with it, the more Russia can do whatever it wants in the international domain.

However, even Russia doesn't want nuclear war. It doesn't take many nuclear bombs being dropped to plunge the world into a nuclear winter and crisis. Things can get out of hand quickly. Even Russia doesn't want that level of chaos.

While it might be in Russia's interest to let this situation fester, I don't see that as a factor leading to nuclear escalation beyond the general risk inherent in allowing chaos. I don't view it as a major factor increasing the risk of actual nuclear war, though Russia does indeed love chaos.

Nuño Sempere

00:24:27

I don't see that as a major factor either. It doesn't have to be a large nuclear weapon resulting in nuclear winter. A small tactical weapon could be used. However, you wouldn't want to bomb a region you consider your own.

Lisa

00:24:50

From my point of view, there's a very tiny chance this could escalate out of control. Vidur sees a higher potential risk. Nuno, you and I are at very similar probabilities, though you might be edging slightly higher than I am that something could go out of control. Vidur is perhaps looking at broader possibilities for how this conflict could go.

We always have to ask this question when nuclear-armed powers are involved; it's a reasonable question. We are concerned with the potential for catastrophic events, but I believe we would all agree that the overall chance here is very low.

Nuño Sempere

00:25:37

Agreed.

Vidur Kapur

00:25:38

Yes.

Rai Sur

00:25:39

It's good to know that the absolute risk of nuclear weapon use is quite low in all your opinions. What are you looking out for now? What developments would make you significantly update your assessment?

You mentioned the thousand-uniform-death line you forecasted. Are there other indicators in that realm, or what else are you considering?

Lisa

00:25:59

For me, I'd be watching how much this escalates conventionally. If we saw a thousand military deaths, it would be clear the conflict is escalating.

However, even then, I wouldn't substantially increase my personal estimate of nuclear war risk. I might go up by 0.1% because any conflict increases risk. Even with a thousand total military deaths on both sides, I would still expect the conflict to escalate conventionally and not move to nuclear.

Vidur Kapur

00:26:35

I'm also looking for military deaths, particularly since we've mainly seen civilian deaths so far. I'm watching how prisoners of war are treated, if any are taken. For instance, if Indian pilots are captured, how are they treated? Will they be sent back to India or detained? And how would India respond?

I’m observing the extent of Pakistan's retaliation, or its expected retaliation, against India. Airstrikes would likely be used, though we've already seen artillery. Will they escalate, or respond in kind, doing something similar to India's actions? If a Pakistani jet is shot down, what happens then?

There's also a tail risk from social media. A lot of information and rumors circulate, which has always been true in war, but social media amplifies it. People believe what they see on social media, which can exacerbate situations and potentially lead to poor decision-making. I'm watching whether anything big and sensational is reported on social media and how policymakers grapple with that.

Nuño Sempere

00:28:09

I'm also observing the strength of the Pakistani state relative to terrorist groups in its territory. A big warning sign would be either side changing its military doctrine on nuclear weapons. Russia, for example, changed its doctrine a few times during the war in Ukraine to make deployment easier; that would be a significant warning.

I'll also watch how much independence both sides grant their commanders in operations. If India, or Pakistan, grants commanders full military independence, they could potentially use nuclear weapons.

I’m still monitoring whether Balochistan will make a play for independence amidst chaos and confusion. Afghanistan has been supporting Islamic resistance or terrorist groups in the region, so I'm curious how that develops.

A possibility is that the situation calms down, but the Pakistani state doesn't effectively assert itself against terrorist groups in the region, leading to a repeat of what we've seen for the last couple of decades. These are a few things on my mind.

Rai Sur

00:29:26

I think that's a great place to wrap up. Thank you, everyone.

To our listeners, I hope you enjoyed this discussion. If you have any feedback, please send it to podcast@sentinel-team.org. We will see you next time.