China Allegedly Tested a Nuclear-Capable Hypersonic Weapon. Now What?

Revelations over a secret Chinese weapon test have stoked fresh fears in Washington that the two nations are approaching a strategic crossroads amid a sweeping build-up of Beijing’s nuclear arsenal.

The Chinese military, in the midst of a complete modernization of its strategic forces, is expected to at least double its number of nuclear warheads over the next decade. It has quietly constructed hundreds of new silos capable of launching long-range ballistic missiles. Now, U.S. officials say, China is fine-tuning the design of a new lightning-quick weapon system engineered to evade America’s multi-billion-dollar early warning and defense systems.

The Financial Times reported on Oct. 16 that a Chinese rocket this summer carried a sleek spacecraft into orbit where it separated, circumnavigated the globe, then re-entered the atmosphere at blistering speeds before plunging back to Earth. Although the glider reportedly missed its target by about 25 miles, the error would be negligible if, say, it was carrying a thermonuclear warhead targeting an American city.

The report sent tremors through U.S. national security circles because such a weapon, known as a “hypersonic glide vehicle,” came years before analysts believed China would be able to develop it. The term “supersonic” means that an object is traveling faster than the speed of sound, or Mach 1. The term “hypersonic” means a vehicle is going five times that speed or more. The U.S. currently has no way to stop such a weapon, especially if it were maneuverable.

Joint Chiefs of Staff Chairman Gen. Mark Milley told Bloomberg Television on Oct. 26 China’s test was “very concerning.” He compared the event to 1957 when the Soviet Union successfully launched Sputnik, the world’s first satellite, that revealed the U.S. was behind in the space race. “I don’t know if it’s quite a Sputnik moment, but I think it’s very close to that,” he said. “It has all of our attention.”

What the test demonstrates is that China, like Russia before it, is intent on designing nuclear weapons that aim to nullify America’s globe-spanning missile defenses. Today’s systems are designed to blast apart nuclear-tipped intercontinental ballistic missiles (ICBMs) that fly high into space releasing warheads which fall in a predictable, parabolic arc toward a target. A maneuverable weapon hurtling toward a target at hypersonic speeds is impossible for existing U.S. defenses to shoot-down.

The adversaries’ cat-and-mouse weapons developments, reminiscent of the Cold War, comes as China and the U.S. face off in hot spots like Taiwan, where the risk of miscalculation could catastrophically result in direct conflict. Unlike during the Cold War, the U.S. and China have failed to establish a robust series of treaties—which the U.S. and Soviet Union had in place—to keep communication channels open and growing weapons arsenals in check.

China’s new demonstrated capability does not yet fundamentally change the balance of military power, U.S. officials and analysts say, but it does underscore Beijing’s rapid expansion and diversification of its nuclear arsenal and should motivate the Biden Administration to meaningfully engage Beijing in non-proliferation talks. What’s needed is military transparency and diplomatic verification before these new weapon systems are fielded and become more challenging to control.

“We absolutely should find ways to engage China on nuclear arms control,” says Andrew Weber, who spent 30 years on nuclear-weapons issues in the State and Defense departments before retiring in 2015. “I am especially concerned that China might deploy so-called ‘nuclear war fighting systems,’ like nuclear-armed cruise missiles. We have a window of opportunity to prevent that through negotiations.”

Persuading China to limit its capabilities will not be easy. Even if Beijing doubles its stockpile over the next decade, as U.S. intelligence assesses it is on track to do, it will represent a fraction of those belonging to Washington and Moscow. Russia and the U.S. are capped at 1,550 deployed nuclear warheads under a bilateral treaty known as New START. China, however, is not part of that agreement and only has an estimated stockpile consisting of more than 200 warheads. China became a nuclear weapons power in 1964, but has restrained its strategic expansion—until recently. The nation is unlikely to want to limit its newfound capabilities to attack from land, air, and sea, which Russia and the U.S. have built-up over decades.

“These developments raise concerns about China’s nuclear intentions and signal the pursuit of significant expansion of the diversity and size of China’s nuclear arsenal,” says Shannon Bugos, a research associate at the non-profit Arms Control Association. “The (hypersonic) test highlights the importance of opening a dialogue with Beijing on matters related to strategic stability that is aimed at reducing the risk of conflict and escalation, increasing transparency, and tackling concerns that inspire the development of such systems in the first place.”

The Biden Administration has refused to comment directly about China’s alleged test. In fact, officials have said little overall about China’s increased nuclear weapons capacity and strategy. The White House may be awaiting the results of the Nuclear Posture Review, a policy document for the U.S. nuclear arsenal that every new administration produces after a top-to-bottom evaluation.

But the review underway hasn’t stopped Republicans from weighing in. “China’s test of a nuclear-capable hypersonic glide vehicle is one more milestone in China’s military modernization—designed to intimidate and bully the West,” Sen. Jim Inhofe of Oklahoma, the top Republican on the Senate Armed Services Committee, said on Facebook on Oct. 18, two days after the Times report. “This is just the latest in a string of high-profile revelations about China’s rapidly growing nuclear arsenal.”

For decades, the strategy of Republican and Democratic Commanders in Chief alike to prevent nuclear war and the spread of weapons to non-nuclear states has been to reduce nations’ nuclear arsenals and forge new arms-control agreements. President Joe Biden told world leaders at the United Nations last month the U.S. was “not seeking a new Cold War or a world divided into rigid blocs,” echoing what happened with the Soviet Union.

But by any measure, Washington’s relations with Beijing have been getting worse, not better. CIA Director William Burns this month called China the “most important geopolitical threat we face.” His agency announced the creation of a top-level working group on China as part of a sweeping effort to challenge Beijing, echoing previous responses to the threats from al-Qaeda and the Soviet Union. The Defense Department often refers to Beijing as “America’s pacing threat,” around the Pentagon. “It means that China is the only country that can pose a systemic challenge to the United States in the sense of challenging us, economically, technologically, politically and militarily,” Colin Kahl, the undersecretary of defense for policy, said in June.

The largest potential flashpoint is currently in Taiwan, which politically split from the mainland in 1949 following China’s civil war. Earlier this month, Chinese President Xi Jinping vowed to pursue a peaceful reunification with the island, and Beijing has sent nearly 150 warplane sorties into Taiwan’s Air Defense Zone in recent weeks.

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The U.S. has consistently hinted it would defend Taiwan from Chinese attack but hasn’t publicly committed to intervene—the idea being that Beijing, amid the ambiguity, will not invade for fear of wider war with the United States. Earlier this month, however, the Wall Street Journal reported that around two dozen U.S. special operations troops and Marines have been training Taiwanese forces for over a year, having first been dispatched by the Trump Administration.

China wants to alter that U.S. calculus in the Asia-Pacific region, said Timothy Heath, a senior international defense researcher at the RAND Corporation. The nation’s military expansion, he said, demonstrates it can hurt the U.S. at home or abroad. “This hypersonic weapon adds to the growing inventory of Chinese nuclear-strike capabilities,” Heath said. “That, by itself, isn’t necessarily a game-changer, but what it suggests China is trying to raise the risk and cost of a potential conflict so high that the U.S. starts to rethink some of its regional security commitments.”

Beijing, for its part, insists the alleged hypersonic weapon test wasn’t ill-intentioned. Zhao Lijian, China’s Ministry of Foreign Affairs spokesman, called it “a spacecraft, not a missile” at an Oct. 18 press conference. “This test was a routine spacecraft experiment to verify the reusable technology of spacecraft, which is of great significance for reducing the cost of spacecraft use,” he said. “It can provide a convenient and cheap way for humans to use space peacefully.”

Even if China is testing a hypersonic weapon system, it is not exactly a new, futuristic nuclear-armed technology. The Soviet Union deployed a similar system, called a “fractional orbital bombardment system,” in the 1960s. The U.S., Russia and China have all been developing hypersonic weapons programs with mixed success. In May, the Biden Administration requested $3.8 billion for its program in the fiscal year 2022.

The White House is also expected to continue heavily invest in defenses. The Missile Defense Agency received about $162.5 billion from 2002 through 2019, according to the Government Accountability Office. The agency requested about $45 billion over the next four years. As designed, the U.S. ground-based missile defense system is set up to intercept one or two ballistic missiles headed for the United States. There are just 44 interceptors, all arrayed in California and Alaska. The idea is if a rogue nation, such as North Korea—which is known to have limited numbers of ICBMs—launched a missile toward an American target, it could be destroyed before striking down.

But China, with an estimated arsenal of more than 100 ICBMs, could do far more damage. If it wanted, Beijing could easily overwhelm the U.S. system by blasting off dozens of missiles. What keeps them in-check, the argument goes, is the expectation that if it launches a nuclear strike, it will have to deal with the repercussions. The theory, known as mutually assured destruction (MAD), is what military planners have banked upon since the dawn of the atomic age.

“Do we accept mutual deterrence with China? If we do, then (the hypersonic weapon) doesn’t matter,” said Jeffrey Lewis, a nuclear weapons analyst with the James Martin Center for Nonproliferation Studies in Monterey, Calif. “But a lot of people in the Pentagon don’t accept mutual deterrence. They do think our missile defenses can help take China’s deterrent away. For those people, this is a big deal. And for the rest of us, we’re hostage to the arms race.”