Even a casual observer of the contemporary global strategic environment will concur that nuclear weapons are very much back in the picture as several countries – including the United States and China – seek to modernize their arsenals and develop new capabilities. With many nuclear powers pushing their envelope and, in some cases, luck, and the future of arms control under stress, the current nuclear environment is defined by several challenges around proliferation and escalation risks.

To understand them better, The Diplomat spoke to Vipin Narang, associate professor of political science at the Massachusetts Institute of Technology (MIT) and member of MIT’s Security Studies Program. Narang, also a nonresident scholar in the Nuclear Policy Program at the Carnegie Endowment for International Peace, is author of “Nuclear Strategy in the Modern Era” (Princeton University Press, 2014).

In your opinion, what are the top three nuclear challenges the world faces today?

First, vertical proliferation, and specifically renewed great power nuclear competition and arms racing, threatens to upset decades of trends that enhanced strategic and crisis stability. Russian and Chinese modernization programs — largely driven by America’s large conventional and nuclear counterforce capability and the unfulfilled fantasy of American national missile defenses — aim to survive an American strike and penetrate defenses. That has led to a variety of programs, including hypersonic glide vehicles, nuclear-powered cruise missiles, and the oldie but goodie — building up mobile capabilities. The US threatens to respond in kind with the withdrawal from the INF Treaty and the prospect that New START is not renewed with Russia. All of these developments threaten to disturb strategic stability.

Second, horizontal proliferation. However, we face not just the looming risk of adversarial proliferation — states such as Iran — but also of allied proliferation, in states such as South Korea, Germany and even Japan, due to concerns surfaced during the Trump administration that the United States may not indefinitely provide credible extended deterrence. In addition, a third class of states, “frenemies” like Saudi Arabia, who have promised to acquire nuclear weapons if their primary adversary (Iran in this case) does are also flirting with the idea and capabilities for at least a nuclear hedge. We may be on the cusp, in the next decade or two, of a cascade of new nuclear weapons powers.

Third, 75 years after the last wartime use of nuclear weapons, today’s nuclear weapon states seem less chastened by the prospect of nuclear use and escalation and are increasingly “pushing the line” against other nuclear weapons powers, attempting to break free of the constraining effects of being deterred. The last year has seen some disturbing “firsts”: India bombing the undisputed territory of another nuclear weapons power at Balakot for the first time in history, and Turkey — an American ally which hosts US nuclear weapons at Incirlik — firing at American troops. The problem with the threat that leaves something to chance, is that… it leaves something to chance. And as nuclear states push the line against other nuclear states, even if they do not want a war… war may find them. That is, nuclear powers are increasingly running the risk that they may stumble into a war, and that would put us in uncharted territory.

You have warned against Trump’s North Korea strategy (if one can call it that) and have been consistently pessimistic about the prospect of denuclearization there. As a new administration takes over in January, what advice would you give the new president about Kim Jong Un and his nukes?

I have long argued that Kim Jong Un will not voluntarily surrender his nuclear weapons program and taking it away by force — as some like John Bolton [the former US national security advisor] continued to advocate even after North Korea tested an ICBM and purported thermonuclear weapon — is exceptionally dicey. But that does not mean that we cannot try to slow down the growth of the program, seek caps on certain capabilities, and keep the rhetorical fiction of denuclearization of the Korean Peninsula as an end goal that we accept is unlikely to ever be achieved.

In fact, it appears that this deal — Yongbyon in exchange for some sanctions relief — was on the table at Hanoi. If verified and completed, that would have shut off North Korea’s only known source of plutonium and tritium production, and a nontrivial proportion of its uranium enrichment. This could have slowed the growth of the nuclear program and shaped the future composition of the force by starving it of further plutonium and potentially tritium (for thermonuclear weapons). But Trump walked away, claiming it was too small a deal. Instead, we got no deal and Kim Jong Un continues to expand and improve his nuclear and missile force.

I suspect we will look back at Hanoi with regret, though it is possible a similar deal may resurface. If it does, I believe we should take it. Slow, cap, rollback, and eliminate (even if we never get there) for corresponding measures, in tandem, is a sensible formula to manage a nuclear North Korea.

We recently saw North Korea flash a new missile capability during its annual parade. Any thoughts on what the missile may portend in terms of where Kim sees his nuclear capabilities going in the future?

For a year, Kim Jong Un had been promising a “new strategic system,” and on October 10 we discovered that it was a new heavy transportable liquid fuel ICBM, based on its Hwasong-15 ICBM. This new missile is one of the world’s largest mobile liquid fuel missiles and the key feature is the large payload it can seemingly deliver, such as potentially penetration aids or multiple warheads, to defeat American national missile defenses — which may not work well today, but which adversaries such as Russia, China and North Korea fear may work tomorrow.

This new missile was not a surprise, and largely represents a continuing evolution of North Korea’s growing missile and nuclear capabilities. It is designed to solve one of two North Korean strategic problems: penetrating American missile defenses. There were questions about whether North Korea could develop warheads compact enough for MIRVs (multiple warheads on a single missile), but the size of this missile obviates some of that problem — your cars can be bigger if you build a gigantic garage. However, the missile is so big and slow, and takes so long to potentially fuel, that it may exacerbate the other problem — survivability — but I think we should fully expect that North Korea is also working on capabilities to address that concern, such as a mobile solid fuel ICBM that is easier to hide and prompter to launch. In fact, we may have seen tantalizing hints of that capability as well in the parade, and that would represent a bigger leap for the program. In any event, these developments and improvements — which are still away from being operational — are precisely what “normal” nuclear powers do, and further suggests that Kim Jong Un has no intention of surrendering his nuclear weapons program.

We have heard a lot from the Trump administration of late about China’s nuclear ambitions. How do you assess the trajectory of China’s nuclear weapons and delivery platforms, as well as its doctrine?

Let’s start with the facts: China has maybe 200 nuclear weapons that can range the continental United States, very few of which are deployed during peacetime. The United States, by contrast, has well over a 1,000, depending on your accounting, that are ready within minutes to range mainland China. This does not even account for the warheads in the stockpile that can be quickly uploaded to American ICBMs and SLBMs which are not fully MIRV’d under New START. So even a doubling of China’s strategic nuclear force still leaves it multiples lower than the United States and Russia.

My main reaction to Chinese nuclear modernization is: What took it so long to start? For decades, it lived with a posture of “plausible retaliation” with maybe two dozen ICBMs that could range the continental United States. With growing conventional and nuclear counterforce capabilities, and the unrelenting pursuit of national missile defenses — which can in combination threaten to neutralize China’s second strike capability, by eliminating a large portion of the ICBMs and relying on missile defenses to intercept the residuals — the question is why China only started investing in mobility and numbers and penetration aids/hypersonics in the last decade or so. To me, all of these developments are China’s delayed effort to guarantee assured retaliation. China’s massive buildup in conventional short-range ballistic missile capabilities obviates the need for it to rely on nuclear weapons in a theater scenario, though scholars such as Caitlin Talmadge have pointed out that we cannot sleep on the risks of inadvertent Chinese nuclear escalation. But, I see continuity in overall strategy, and a delayed effort to develop the capabilities and deployment patterns — mobility, penetration, SSBNs — to implement that strategy with greater assurance.

What do you make of the hype around hypersonics? What about claims around artificial intelligence and nuclear command and control?

The pursuit of hypersonics is again driven by the unfulfilled fantasy of working national missile defenses. Presently, long range missile reentry vehicles, and certainly maneuverable reentry vehicles, which are decades-old technology, are perfectly sufficient to penetrate American missile defenses. And all of these reenter the atmosphere at hypersonic speeds. The advent of the new generation of hypersonics are actually slower than long range reentry vehicles. But some are air breathing and can maneuver and porpoise at very high altitudes in the event missile defenses ever work. So, at least in the medium term, I’m a skeptic that these capabilities fundamentally alter the strategic balance. Russia and China do not face a penetration problem at the moment, so hypersonic glide vehicles only have marginal value at the moment.

Similarly, there is a lot of hype over AI and command and control, but a lot remains to be seen whether it affects a state’s ability to maintain command and control or disrupt it. AI may help solve some detection and ISR problems, but the general cat-and-mouse game of emerging technologies and counter-responses is a decades-old phenomenon.

What do you think about future arms control measures for emerging technologies?

Like all arms control measures, the empirical record suggests they will emerge and be adhered to when both states view them as being in their interests, which is unsatisfying and tautological but also the reality. States with an asymmetric advantage in a particular technology will oppose limits on it, while those that fear it will seek those limits. The zone of overlap generally emerges when both or all sides perceive a benefit in capping or limiting that capability — either amongst themselves or collusively to prevent the diffusion of technology to other states. I am not an arms control skeptic so much as an arms control realist.

How do you assess the prospects of the New START treaty being extended, if Trump is reelected next month?   

Ultimately, I do think New START will be extended no matter who wins the election. I think the Trump administration is attempting to play chicken with New START to try to pressure Russia into limiting, for example, its tactical nuclear weapons capability. But ultimately, a New START extension is in America’s interest: arms controllers love it because it is arms control and counter-forcers should love it because it provides a cap and accounting on the systems they have to eliminate. The only constituency that opposes New START are arms racers who believe that an arms race with Russia is good and easy to win. But in the current economic climate, there may be little appetite for a renewed arms race, or even persistent uploading of warheads from the stockpile. And Russia has an interest in New START for similar economic and management reasons. It is possible that a second Trump administration would only extend New START for one year and attempt to negotiate something stronger or multilateral in that year — he may in fact try to do this before the election itself. I do not think there is any chance of China joining a multilateral equivalent of New START — it would either be an invitation for it to build to parity with the US and Russia, or force it to agree to inequitable limits, which it will never do. But I do think we will see an extension of the bilateral New START at the end of the day. But whether it is for one or five years remains to be seen.

Would a Biden administration, come January, roll back some of Trump’s nuke modernization plans?

The Democrats, in general, seek a safe, secure, and effective nuclear deterrent for the United States and America’s allies at an affordable cost. Although there was a loose bipartisan consensus for the modernization program, there are some components that may be revisited. For example, the ICBM replacement, the ground based strategic deterrent, could be forsook for another life extension of Minuteman III, which may save some cost. I do think certain capabilities, such as the low yield SLBM and the nuclear sea launch cruise missile, could be rolled back. But those are not so much part of the modernization program as particular capabilities that the Trump administration believed filled a “deterrent” gap, which I suspect many in a Biden administration remain unconvinced ever existed

To your mind, have India and Pakistan learnt the wrong lessons about escalation after India’s February 2019 Balakot air strikes and Pakistan’s retaliatory action?

I hesitate to judge what lessons either side may have privately taken away from Balakot, but at least publicly both sides seem to underestimate the role that pure luck played in keeping the crisis from further escalating. I think, for example, that if Indian fighter pilot Abhinandan Varthaman had been killed when his MiG-21 was shot down, or if he had died in Pakistani custody, or if there was a delay in his return and Prime Minister Narendra Modi carried out an alleged surface-to-surface missile strike, the crisis could have quickly escalated as domestic political pressure to hit back boiled over. Even in this case, where neither state wanted a broader war, both sides do seem to underestimate the risk that they came very close to stumbling into one. In general, India’s frustration with Pakistan’s continued use of terror against the Indian homeland is leading it to see how far it can “push the line” against another nuclear weapons power. That frustration is understandable, but it does not mean that pushing the line is risk-free.

I am disappointed you did not ask me about my hobby horse: the sanctity of India’s No First Use (NFU) declaration! At this point, no one believes the absoluteness of India’s NFU declaration — though it sort of remains official doctrine — including, most importantly, India’s government itself.