WASHINGTON — During the Cold War, American strategists feared the Soviet Union was outpacing the United States in arms production, potentially leading to a so-called missile gap. Now, U.S. officials are worried about a literal gap called near space and China’s growing presence there.
High above earth, but below orbiting satellites, the United States and China are testing new defense systems. China’s exploitation of the zone with aerial craft and advanced munitions suggests it is pulling ahead of its superpower rival in important ways.
This little-known and little-seen strategic contest over near space — a phrase that is suddenly on the lips of every other American politician and policymaker — is increasingly critical for the honing of advanced warfare and certain types of espionage.
Near space is liminal space, a stratospheric netherworld where no international law applies and no military force holds dominance, where hypersonic missiles and space planes fly and surveillance balloons drift without being picked up by radars.
The Chinese military, which has surprised the United States with uses of hypersonic missiles and balloons, has focused for years on developing capabilities in near space, generally thought of as 60,000 feet to 330,000 feet above earth — or 11 miles to 62 miles — where no civilian aircraft fly.
U.S. military commanders, policymakers and legislators warn that China may have surpassed them in thinking strategically about that zone and in deploying assets, and that the United States needs to address looming issues there.
In a speech on Thursday on the alarming episodes involving the spy balloon and three unidentified (but likely innocuous) flying objects, President Biden said he would ask Secretary of State Antony J. Blinken to work toward establishing “common global norms in this largely unregulated space.”
That will become more urgent as superpowers vie to establish footholds in high-altitude gray areas.
“We should be taking Beijing’s ‘Red Zeppelin’ program seriously,” said Matthew Pottinger, a deputy national security adviser in the Trump administration, using a nickname for China’s spy balloon program.
“The Chinese military has written about a range of potential applications for balloons and drones in near space,” he added. “You can intercept communications that you can’t capture from space. You can loiter for longer periods of time over targets, study or interfere with an adversary’s radar, target enemy satellites and help guide strategic weapons.”
What We Know About the Objects Shot Down Over the U.S. and Canada
An aerial mystery. The United States and Canada have shot down three unidentified flying objects over North America in recent days. The incidents came after the United States blasted a Chinese spy balloon out of the sky on Feb. 4. Here is what we know about the objects:
What happened? The U.S. military intercepted an unidentified flying object on Feb. 10 over the Arctic Ocean near Alaska, another on Feb. 11 over the Yukon Territory and a third over Michigan on Feb. 12. American and Canadian officials are still trying to identify and recover the objects.
Why were these objects shot down faster than the balloon was? The Chinese spy balloon, which traversed the United States for days before it was taken down, was flying at 60,000 feet and didn’t pose a danger to aircraft. U.S. officials said that the three unidentified objects posed a “very real” threat to civilian aircraft but were not sending out communications signals.
How are the objects different from the spy balloon? U.S. officials said that the objects over Alaska and the Yukon were smaller than the spy balloon. They also said that the Yukon object was cylindrical, while the object over Michigan had an octagonal structure with strings hanging off. A top White House official also noted that the objects might turn out to be harmless commercial or research efforts.
Chinese military researchers have warned in recent years of the need to keep the United States from establishing superiority in near space. In 2018, Liberation Army Daily, the official newspaper of the Chinese military, published an article that said, “Near space has become a new battleground in modern warfare.” The same newspaper said in 2020 that “some countries across the world have been accelerating the pace of near-space weapons research,” adding that near-space airships “are not constrained by orbital mechanics and do not need expensive surface launch facilities.”
Chinese military researchers have said that airships could be a potential alternative to satellites, including if satellites are knocked out in war. Last year, China experimented with using rockets to send balloons up to 25 miles above earth.
A part of the Chinese military called the Strategic Support Force most likely oversees near-space programs, said John K. Culver, a former U.S. intelligence analyst on China. It reports directly to the Central Military Commission, whose chairman is Xi Jinping, China’s leader, and is equal to other branches of the military. It supervises space programs, intelligence collection of electronic communications and cyberoperations.
But while Chinese military officials speak anxiously of American expansion into near space, the U.S. government has in reality not paid much attention to that zone, according to current and former U.S. officials. That is partly because the military and intelligence agencies have used space-related budgets to deploy assets into far-flung outer space — for example, the many U.S. government surveillance satellites that circle the globe.
The result is the United States lacks intelligence-gathering and defense capabilities in near space, the current and former officials say.
“We know how to detect them, we know how to track them, and we know how to kill them. We just weren’t looking for them,” said Adm. William E. Gortney, a retired commander of the U.S. Northern Command and the North American Aerospace Defense Command, or NORAD, and a former Navy FA-18 fighter pilot. “This goes to finding our seams and where the enemy resides within those seams.”
A classified U.S. intelligence report sent to Congress last month indicated that the military had spotted unidentified flying objects at many altitudes, including possibly in near space, U.S. officials said.
Some lawmakers have suggested that they intend to put a spotlight on near space — and perhaps get more in the defense budget for those efforts. “It is essential that we provide the military and intelligence community with the necessary resources to detect and monitor objects in near space,” said Senator Kirsten Gillibrand, a New York Democrat on the Armed Services Committee.
The altitudes of near space are ideal for certain military systems, ones that China appears to have an upper hand in innovating.
The 200-foot-tall Chinese spy balloon was operating at the sweet spot for surveillance balloons, said Mark J. Lewis, the former chief scientist at the U.S. Air Force. Higher altitudes would have required a far bigger and heavier balloon; any lower, and the atmosphere’s winds would buffet it far more.
But even at the spy balloon’s drifting altitude of 60,000 feet, winds were a problem and appeared to have blown it off course from its intended targets of U.S. military bases in Guam and Hawaii, U.S. officials say.
During the Cold War, the U.S. military and intelligence agencies experimented with balloons to conduct surveillance and spread propaganda. One balloon, part of Project Mogul, was designed to fly high and search over long distances for weak reverberations after a nuclear test. When one of the balloons crashed near Roswell, N.M., the government allowed the spread of conspiracy theories about an alien crash to help cover up the story.
The U.S. military began looking more closely into balloon use two decades ago, wondering if modern science could turn an occasional tool of the Cold War into a more effective collection device.
Balloons are intriguing because they are low cost and can loiter over an area for longer than a satellite, Dr. Lewis said. But balloons are hard to control. Adding propulsion systems that can counter atmospheric effects weighs them down and leaves less room for collection devices.
“We had looked at all sort of ways to control them with propulsion,” he said. “So that becomes a problem because propulsion requires engines. Engines require power. Power means weight, and balloons don’t like weight.”
Hypersonic munitions — a new, advanced type of weapon that Chinese, Russian and U.S. militaries are all developing — work well in the relatively low-pressure and low-density environment of near space, where cold temperatures also help keep the missiles from overheating.
The weapons can maneuver at speeds above Mach 5 and are much harder to detect and shoot down. The Pentagon is developing hypersonic cruise missiles and gliding warheads that will fly above 80,000 feet, the upper range of what most air-defense missiles can reach.
China appears further along. It has conducted more than 200 hypersonic missile tests, a former U.S. official said. In 2021, Pentagon officials were stunned by two Chinese tests of a nuclear-capable hypersonic missile delivery system that first put the weapon into orbit in space, then enabled it to detach and descend through near space to earth.
Gen. Mark A. Milley, the chairman of the Joint Chiefs of Staff, said at the time that the tests were “very close” to a “Sputnik moment” for the United States.
China and the United States are also developing space planes, which would fly at orbital altitudes as well as in the near-space zone and could be used for logistics and intelligence-gathering missions, as well as potential armed sorties in wartime. The parameters of the U.S. experimental space plane, the X-37B, remain classified.
A big question looms over 21st-century space-based defense: how to define where the Pentagon’s war-fighting airspace ends and space begins.
That is complicated by the fact that there is no legal, accepted definition of where the boundary lies. Until now, international rule makers did not see urgency in delineating that because few technologies could operate in the near-space zone, and debating laws and norms for outer space seemed more important, said Julian Ku, a scholar of international law at Hofstra University.
Without sovereign boundaries or international laws governing the zone, militaries will be unsure where they can operate — or maybe claim that anything is permissible.
The U.S. Space Command defines its area of responsibility as beginning at 62 miles above sea level, or about 327,000 feet — otherwise known as the Karman Line, named after Theodore von Karman, a Hungarian American physicist.
“Any definition of where space begins is arbitrary,” Dr. Lewis said. “And anyone who tells you otherwise, they are making something up.”
Victor E. Renuart Jr., a retired Air Force general and the former commander of NORAD, said his “tactical” definition of near space would be 50,000 to 100,000 feet. “Sufficient atmosphere to be maneuverable and for certain engines to function well, certainly for high-altitude balloons and unmanned, lightweight ‘thrusted’ vehicles,” he said in an email.
But the United States does not have adequate sensor coverage in this area, current and former military officials say, as shown by the recent episode involving the Chinese spy balloon. And U.S. officials only discovered China’s broader spy balloon program years after it had begun operating.
“We should expect more of these incursions,” General Renuart said.
After the spy balloon transited the country this month, NORAD adjusted radar systems to make them more sensitive. As a result, the number of detected objects has increased sharply.
But how to decide which high-altitude object is conducting surveillance or was sent by a power with hostile intent?
Even as the United States refines its detection systems, “adversaries will attempt to rapidly shift to other options to drive us to invest more to defend,” General Renuart said.
“This must be a coordinated effort of all agencies of the U.S. government and our allies to thwart,” he said. “And we are late.”
John Ismay and Chris Buckley contributed reporting.