Why New Technology Is Making Nuclear Arms Control Harder

Several senior U.S. military leaders declined interview requests for this article; Defense Department leaders keep current nuclear concerns close to their vest. But in 2019, the Air Force released a collection of papers in which leaders already were lodging concerns. In it, Maj. Jeff Hill, said that newly developed U.S. defenses against Russian and Chinese missiles “has led each of these two countries to aggressively pursue its own [highly-maneuverable hypersonic missile] programs. Russia specifically highlights ‘American military-technological advances’ including its ballistic missile defense program as an area of concern in relation to deterrence,” citing the work of Kristin Ven Bruusgaard, one of the foremost Western academic experts on Russian nuclear strategy. His work was published as part of a U.S. Air Force Center for Strategic Deterrence Studies student research project that assessed the influence of hypersonic weapons on deterrence.

All this makes preparing for and deterring nuclear war a great deal more complex than it was during the 1950s and 1960s.

“There’s a number of very fundamental assumptions that we have made over the last 30 years, that really are no longer valid,” said Adm. Charles Richard said at September’s Deterrence Symposium. Richard leads U.S. Strategic Forces, or STRATCOM, which oversees the military’s nuclear arsenal. “After the fall of the Soviet Union and the [U.S.] success in Desert Storm, we achieved a national security environment where, I would argue that, the risk of a strategic deterrent failure, and, in particular, the risk of a nuclear deterrence failure, was low…. We started taking it for granted and forgot all the things that we had to do, from a strategic deterrence standpoint, to get us to that environment to begin with.”

China

One of those assumptions was that China posed an all-but-negligible nuclear threat. In 2006, the People’s Liberation Army had just 18 nuclear-capable missiles that could reach the continental United States; each carried just one warhead.

“If the United States can destroy all of Russia’s long-range nuclear systems in a first strike—as we argue it could possibly do today—it suggests that the Chinese strategic nuclear arsenal is far more vulnerable,” nuclear scholars Keir Lieber and Daryl Press wrote at the time.

But China has since vastly expanded its arsenal; in 2020, Pentagon officials estimated it numbered “in the low 200s,” and could double. It has also built out its own nuclear triad, with nuclear-capable stealth bombers; four Type 094 ballistic missile submarines; and on land, truck-mounted missile launchers and an estimated 300 completed and planned ICBM silos.

The particulars of China’s buildup also introduce new challenges, STRATCOM’s Richard said. For example, U.S. officials believe that the PLA is building more silos than it has ICBMs. But if Pentagon planners don’t know which ones are filled, they must assume they all are. Thus, China deters a nuclear strike with fewer warheads. It’s a different approach than the warhead-for-warhead approach that the United States and the Soviet Union pursued.

And the emergence of a third huge nuclear arsenal complicates deterrence theory, STRATCOM’s Richard said.

“In general, deterrence theory doesn’t really account for a three-party problem. How you do deterrence with three, peer nuclear-capable competitors?” Richard said. “The Cold War was very much a two-party competition.”

Meanwhile, U.S. military planners are changing their definition of “strategic” deterrence, weapons, and attacks. During the Cold War, this almost always referred to nuclear war. But today’s planners use the term to include non-nuclear threats and technologies that could have devastating effects—for example, destroying an adversary’s ability to see an attack coming or respond to it.

“Strategic effects can be much broader than simply ‘nuclear,’ in terms of what could possibly be done in cyber or possibly be done in space, critical infrastructure, information domain, role of allies and partners. All of that, I think, requires a very critical relook,” Richard said.

That nuance is often lost in the contemporary conversation about nuclear weapons and deterrence. In 2018, a New York Times article, “Pentagon Suggests Countering Devastating Cyberattacks With Nuclear Arms” sparked frenzied concern that the United States under President Donald Trump was lowering its bar for launching a nuclear strike. The article had quoted from a draft version of the Pentagon’s 2018 Nuclear Posture Review, with sources saying, “large cyberattacks against the United States and its interests would be included in the kinds of foreign aggression that could justify a nuclear response.”

Officials quickly rushed out to assure the public that the United States was only recognizing that a strategic attack was no longer necessarily nuclear in nature. Technology had created new opportunities.

Robert Soofer, then-deputy assistant defense secretary for nuclear and missile defense policy, told reporters that a strategic attack could include “catastrophic attacks against civilian populations, against infrastructure. It could be an attack using a non-nuclear weapon against our nuclear command-and-control [or] early-warning satellites.”

In February 2021, then-Vice Chief of Staff Gen. John Hyten publicly advised the incoming Biden administration to ensure that the next nuclear posture statement encompass all of the new ways an enemy might be able to launch a “strategic attack.”

Future nuclear weapons, including ICBMs, will likely be part of a complex, interconnected digital architecture, and will likely exhibit “some level of connectivity to the rest of the warfighting system,” ​​Werner J.A. Dahm, then-chairman of the Air Force Scientific Advisory Board, predicted in 2016. His warning came on the eve of a major study by the Air Force to see how trustworthy nuclear weapons would be if they were networked together, a study that was never publicly released.

Super Maneuverable Missiles 

Perhaps the biggest change to nuclear deterrence is the appearance of new types of hypersonic weapons. Unlike Cold-War era ICBMs, the new class of hypersonics that China and Russia (along with the United States) are pursuing are steerable, allowing an adversary to target a much wider space with one missile, and making such missiles very difficult to defend against.

Chinese and Russian hypersonic missiles will be capable of carrying nuclear warheads, but the United States is pursuing hypersonics for precision strike with only conventional, or non-nuclear, warheads.

“We didn’t want to have the confusion. The Chinese seem to revel in that, the Russians as well,” said Mark Lewis, who served in 2020 as the acting defense undersecretary for research and engineering and is now the executive director of the National Defense Industrial Association’s Emerging Technologies Institute.

Still, any country could use a non-nuclear hypersonic missile to strike its adversary’s nuclear command-and-control targets.

U.S. scientists have encountered problems developing maneuverable hypersonics. A conventional ICBM experiences extreme heat for a limited portion of its journey to target, as it is hurtling back toward earth from space. But a highly maneuverable hypersonic weapon experiences very high temperatures for far longer. In the case of boost glide weapons, which ascend like conventional rockets but then maneuver to targets, that high heat comes during descent.

Hypersonic cruise missiles, which the Air Force is endeavoring to build and fire from bombers, travel at high speeds entirely within the atmosphere, which introduces even more technical challenges. But they are the most feared class of hypersonics. “When we would do things like war games, for example, hypersonic cruise missiles proved themselves very, very effective,” said Lewis.

For a time, the United States had the lead in the development of hypersonic cruise missiles but then gave it up, he said. “As the Air Force was formulating its portfolio, going back, you know, five, six years ago, they didn’t focus on the cruise missile. Instead they focused on rocket boost flight. That has since been corrected but that also kind of gave us some delays.”

Air Force Col. John D. Varilek leads the 608th Air Operations Center which would oversee U.S. air assets during nuclear war. Three years ago, Varilek wrote that “the Chinese have watched the start-stop measures of the U.S. hypersonic programs and have mimicked investment in these technologies over an unknown number of years. Exactly when the Chinese initiated hypersonic programs is unknown, but the first successful tests of the Chinese concepts in 2014 have provided a catalyst for more focused U.S. research and development in the hypersonic field.”

The United States, China, and Russia have mostly turned to simulations to test hypersonic flight. China has invested in the wind tunnels required to produce the data needed for simulations, allowing them to achieve some breakthroughs in hypersonic systems. They even claim to have a secret tunnel that will allow their military to simulate conditions up to Mach 30 (though U.S. researchers have disputed that claim).

“In August 2018, the Chinese hypersonic glide system named Starry Sky 2 reportedly flew for 10 minutes at speeds of up to Mach 6 with successful rocket glide vehicle separation and follow-on hypersonic glider flight,” Varilek wrote.

But last July, China shocked the world by conducting an around-the-world hypersonic glide-vehicle and missile test. The Financial Times wrote that the test “suggested the Chinese military could hit targets anywhere in the US with nuclear weapons.” Joint Chiefs Chairman Gen. Mark Milley called the event a near-“Sputnik moment” in the strategic technology race.

The United States has yet to conduct a similar test.

The development of these new “invincible” weapons—as Russian leader Vladimir Putin has called them—has triggered a concurrent arms race for new concepts to defeat them. One U.S. answer has been the use of new satellite architectures to watch hypersonics as they proceed along their flight path, in addition to new sensors and object-finding software to spot things like mobile missile launchers.

The Chinese are also racing to develop hypersonic defenses. Varilek wrote that “scientist Qian Qihu has recently boasted of an ‘Underground Steel Great Wall’ capable of intercepting missiles that were previously too fast to intercept.

Why New Missiles Don’t Replace the Need for Old Ones

So why continue to build ICBMs?

In one sense, eliminating ICBMs, or at least not spending money to build new ones, would be a politically easy decision for the United States. In a 2021 report, scholars from the Federation for American Scientists said that majorities of Americans support alternatives to developing new ICBMs and don’t derive a sense of safety from them. The ICBM leg of the nuclear triad is also often considered the weakest, since missile silo locations are known to the enemy. It’s also the leg that presents the biggest risk of accidental launch, since the U.S. president must decide whether to fire them within minutes of receiving warning of an incoming strike. The commander in chief can wait a bit longer before ordering a nuclear weapons launch from bombers or submarines located closer to their targets.

But Tom Collina, director of policy at Ploughshares Fund, said that any politician, particularly a president, who tries to cut the nuclear arsenal would face swift opposition from the military’s STRATCOM, whose officials have testified publicly in support of nuclear modernization spending for ICBMs.

“It’s another structural reason why it’s so hard for presidents to make changes,” Collina said. “They’re essentially going up against the military brass. And no president wants to be on the wrong side of that.”

Unfortunately, however impressive and terrifying maneuverable hypersonic weapons are, they don’t actually change the strategic equation of needing to keep or replace old ICBMs, Lewis said.

“For a variety of reasons, a hypersonic system doesn’t actually give you a lot of advantages over a [non-maneuverable] nuclear weapon,” he said. “Looking at what China and Russia are doing, where they’re burying hypersonic maneuverable systems and nuclear weapons…that says more about policy than it does about capability. That’s them trying to intimidate. That’s them trying to get our attention. But in terms of how that changes the strategic equation, it doesn’t do a lot.”

Why not? No nation will be able to build enough of them to make a difference, Varilek wrote. “Due to the engineering difficulty and the materials needed, which drive a significant cost for such a program, it is highly unlikely that any country will manufacture these weapons in such a quantity as to threaten the current deterrence status quo.”

During the Trump administration, the United States made an effort to bring China and Russia to the negotiating table to craft a new arms control agreement—to replace the bilateral U.S-Russia New START treaty—that would cover new types of delivery systems.

“The bottom line is: we ran out of time,” said one former White House official who was involved in the process. “The Russians correctly calculated that Biden…would extend New START for five years and sure enough, that’s what he did.”

Russia’s invasion of Ukraine has only heightened military leaders’ concerns about the ability of the United States to deter a Russian or Chinese nuclear attack.

“Today, we face two nuclear-capable near peers who have the capability to unilaterally escalate to any level of violence, in any domain worldwide, with any instrument of national power, at any time,” STRATCOM’s Richard told lawmakers last week. “Every operational plan in the Department of Defense and every other capability we have rests on an assumption that strategic deterrence is holding and in particular that nuclear deterrence is holding.”

“If strategic or nuclear deterrence fails, no other plan and no other capability in the Department of Defense is going to work as designed,” he said.