On Thursday, the Pentagon said it was tracking a Chinese spy balloon flying across the US. They may not hold the same intrigue as a buttonhole camera or arsenic hidden in a tooth, but spy balloons have been used for centuries – and, experts say, their use is likely to increase in future.
What happened above the US on Friday?
A suspected Chinese spy balloon has been flying over the United States for a couple of days, US officials said, ahead of a planned trip to Beijing by US secretary of state Antony Blinken.
Fighter jets were readied but military leaders advised President Joe Biden against shooting the balloon out of the sky for fear debris could pose a safety threat, advice Biden accepted, US officials said.
The Pentagon said in a statement: “The balloon is currently traveling at an altitude well above commercial air traffic and does not present a military or physical threat to people on the ground.”
Later on Thursday, Canada’s National Defence released a statement saying that it was monitoring a “potential second incident”.
What are spy balloons?
A contemporary spy balloon is a piece of spying equipment, for example a camera, suspended beneath a balloon that floats above a given area, carried by wind currents. The equipment attached to the balloons may include radar and be solar powered.
Balloons typically operate at 24,000 metres – 37,000 metres (80,000-120,000 feet), well above where commercial air traffic flies – airliners almost never fly higher than 12,000 metres.
Why use spy balloons rather than satellites?
“For the last few decades, satellites were de rigueur. Satellites were the answer,” says John Blaxland, professor of international security and intelligence studies at the Australian National University and the author of the book, Revealing Secrets. But now that lasers or kinetic weapons are being invented to target satellites, there is a resurgence of interest in balloons. They don’t offer the same level of persistent surveillance as satellites, but are easier to retrieve, and much cheaper to launch. To send a satellite into space, you need a space launcher – a piece of equipment that typically costs hundreds of millions of dollars.
Balloons can also scan more territory from a lower altitude and spend more time over a given area because they move more slowly than satellites, according to a 2009 report to the US air force’s Air Command and Staff College.
When were they first used?
The French are the first recorded users of reconnaissance balloons, initiated at the Battle of Fleurus against Austrian and Dutch troops in 1794, during the French revolutionary wars. They were also used in the 1860s, during the American civil war when Union men in hot air balloons, binoculars at the ready, would try to gather information about Confederate activity further away. They sent signals back via morse code or a “piece of paper tied to a stone”, says Blaxland.
The US has revived the idea in recent years, but has tended to use balloons only on US territory.
“Over somebody else’s atmosphere, you are required to seek permission,” Blaxland says. “Or if you’re going to do it [without permission] then expect that it won’t be well received.”
The Pentagon itself said in its short statement on Friday that: “Instances of this kind of balloon activity have been observed previously over the past several years.”
Craig Singleton, a China expert of the Foundation for Defense of Democracies, told Reuters that such balloons had been widely used by the US and Soviet Union during the cold war and were a low-cost intelligence gathering method.
Why is China doing this?
Blaxland thinks it’s unlikely that the Chinese weren’t expecting to be caught: being caught was probably the goal, with two outcomes in mind. The first reason the balloon was launched, he believes, was to embarrass the US, and all the better if it captured some intelligence along the way.
“It’s hard to think how they could have thought that it wouldn’t have been detected. American airspace is so closely studied, by the US civil aviation authorities, by the US air force, the US space force, the weather networks – it’s extremely scrutinised airspace,” he says.
The second reason is to make the US aware of the fact that China has been secretly keeping up with its technology and replicating it.
“Chinese security agencies are masterful at copycat behaviour. They’re very, very good at establishing what technology is and then seeking to replicate it,” Blaxland says.
It’s a case of “anything you can do we can do better”, and is “just the tip of the iceberg”, says Blaxland. China’s spying happens “on an industrial scale”, with small bits of intelligence gathered and transmitted in countless ways. Together, these form detailed pictures.
Singapore-based security analyst Alexander Neill told Reuters that while the balloon was likely to provide a fresh irritant to China-US ties, it was probably of limited intelligence value compared with other elements China’s modernising military has at its disposal.
“China has its own constellation of spy and military satellites that are far more important and effective in terms of watching the US, so I think it is a fair assumption that the intelligence gain is not huge,” says Neill, who is an adjunct fellow at Hawaii’s Pacific Forum thinktank.
What can we expect in the future?
“There’s no limit to what kind of technology you can stick at the bottom of the balloon,” says Blaxland.
“The whole point is higher ground. Strategists and military campaigners talk about dominating the higher ground. And in this day and age, it’s been space. With space now being so congested and contested and now so vulnerable, that sub-space domain, the upper atmospheric domain, has developed a whole new utility and importance for international surveillance and espionage that we had thought was passed and is obviously back, centre stage,” he says.
• This article was amended on 3 February 2023 to note that the first confirmed use of spy balloons was by the French in 1794 rather than by the Union side in the US civil war.
