Old-School Balloons Emerge as Possible High-Tech Spy Tools for China

Issuing a rare expression of regret in response to U.S. criticism, China’s government on Friday said the balloon was designed for meteorological research and blew far off course. The statement did nothing to tame the fury in Washington, and Secretary of State

Antony Blinken

on Friday postponed a trip to Beijing that was designed to put a floor under a much-deteriorated relationship between the superpowers.

The episode has stirred broader questions including, why a balloon?

Like hot-air balloons for sightseeing, a modern military or commercial balloon can hoist sophisticated apparatus hanging below the bag-like fabric “envelope” that allows it to glide along high-altitude air currents. A photo purportedly of the Chinese craft above Montana appeared to show panels like those that might provide solar power for navigation or eavesdropping equipment. The Pentagon declined to confirm the photos were of the Chinese balloon.

Observation balloons are one of the oldest military spying devices; German crafts posed such a threat in World War I, for example, that the U.S. decorated fighter pilots as “balloon-busters” for firing on them. More recently, military and intelligence agencies have deployed balloons to carry modern sensor technology for communications and surveillance, at far lower costs than equipping satellites and for longer periods than airplanes, said industry experts.

Balloons can linger for far longer over an area than a passing satellite, which has the disadvantage of a predictable orbit pattern that allows activity on the ground to be temporarily adjusted to avoid detection. The U.S. maintains an arsenal of 150 nuclear-armed Minuteman III intercontinental ballistic missiles at Malmstrom Air Force Base in Montana—and said added measures had been taken to shield views as the balloon passed over the state. 

China has publicly cheered balloon-modernization developments at home—emphasizing balloons’ usefulness for civilian purposes like monitoring climate change—with a focus on developing crafts that can operate at altitudes ​above 65,000 feet and ​​toward the edge of space, or up to 330,000 feet above sea level, according to local media reports and think tank assessments. The U.S. military said the Chinese balloon spotted above Montana was roughly 60,000 feet above Earth.

U.S. defense strategy is increasingly driven by not ceding technological superiority to China. Now, the appearance of a possible Chinese reconnaissance craft in U.S. airspace raises the specter of a “balloon gap” being potentially added to a list of concerns about China after it has already demonstrated advanced capabilities in hypersonic missiles and artificial intelligence.

“Hostile balloons drifting over the heads of Americans may add another element to the debate over defense,” said

Byron Callan,

a defense analyst at Capital Alpha Partners LLC.

Frank Montoya,

a former top FBI counterintelligence official, said surveillance by balloon can be thought of as something akin to an unmanned U-2 spy plane in the sense that both offer strategic perspective, and are cheaper and easier to deploy than satellites.

High-altitude photos can provide details of military bases, dams, power stations, infrastructure for fiber-optic networks, locations of server farms, bridges, rail lines, interstate highways—providing an adversary specific data on how, for example, to interrupt the internet, slow military deployments or wreak havoc with the electrical grid, said Mr. Montoya.

“There’s also the psychological aspect of it,” he added. “They did it because they could. And we are alarmed.”

On Twitter, Republican Florida Sen.

Marco Rubio

described China’s airship as “not some hot-air balloon,” referring to how officials have described it as roughly the size of three school buses with the ability to maneuver. Drawing parallels with sustained concern in Washington that Beijing-based ByteDance Ltd. has control of American user data through its app TikTok, Republican Utah Sen. Mitt Romney said, also on Twitter, “A big Chinese balloon in the sky and millions of Chinese TikTok balloons on our phones. Let’s shut them all down.”

Human beings provide the best spying intelligence, says Bill Priestap, a former senior counterintelligence officer, but no one method is perfect. “It’s the totality of information collected that is of the most value,” he said.

Some former U.S. national-security officials said they were nevertheless puzzled at the balloon sighting, noting that China has other more discreet means to collect intelligence on American targets, including hacking. 

Unlike a balloon that can easily be identified as Chinese, said John Hultquist, director of intelligence analysis at Mandiant, a cybersecurity firm, “cyber is pretty unique as a cheap and deniable capability.”

Christopher Wray,

director of the Federal Bureau of Investigation, has likened China’s collection of American business intelligence through cyber espionage and other means to “almost an existential crisis.” 

The word balloon doesn’t appear in a recent 196-page report to Congress by the Defense Department on China’s military capabilities. Instead, November’s annual assessment reviewed its cyber-enabled espionage, counter-space capabilities and nuclear-weapon capabilities in echoing the administration’s view that China is the only U.S. competitor with the intent and, increasingly, the capacity to reshape the international order. 

An Air Force think tank briefly mentioned China’s military balloon pursuits in a 2020 report that also mentioned aerostats, blimp-like crafts that typically remain tethered to the ground. “China is particularly interested in using aerostats and reconnaissance balloons for ‘near-space reconnaissance,’” according to the China Aerospace Studies Institute report. 

Doubt is widespread among policy analysts that China lost control of its balloon as the Foreign Ministry appeared to claim.

It isn’t the first Chinese balloon to float over U.S. territory, according to the Pentagon, and by the time the balloon was spotted over Montana this week it had already crossed Alaska’s Aleutian Islands and western Canada. Taiwan and Japan have likewise reported overflights of their territory by Chinese monitoring balloons.

Beijing’s description of its craft raised additional questions, including how a presumably multimillion-dollar craft would have “limited self-steering capability.” Also, China described the balloon as “a civilian airship used for research, mainly meteorological, purposes” and blamed west to east winds known as the westerlies for blowing it off course.

Westerlies are long-understood permanent winds, and while climate patterns have clear strategic value, for both military as well as commercial uses, most governments make weather data publicly available. “I would be interested whether it really is a weather balloon, and if the Chinese say it is for research purposes then they should share the research,” said Jessica Olcott Yllemo, director of climate-security programs at nonpartisan Washington think tank American Security Project. 

Improvements in gathering weather data and advances in solar and battery technology allow modern balloons to be tracked and steered more accurately and loiter over targets for days or even weeks, according to Russ Van Der Werff, vice president of stratospheric solutions at Sioux Falls, S.D.-based Aerostar, which makes balloons and manages their flights for government agencies including the Pentagon and the National Aeronautics and Space Administration.

“We’re not missing any balloons,” said Mr. Van Der Werff

— Dustin Volz and Warren Strobel contributed to this article.

Write to James T. Areddy at [email protected], Doug Cameron at [email protected] and Aruna Viswanatha at [email protected]