Chinese Spy Balloons Are a Sign of Weakness

China’s spy balloons don’t make a lot of sense. At least not from a military perspective.

A high-altitude balloon doesn’t do much that a small satellite in low-Earth orbit can’t do — and the satellite has the benefit of being practically invisible to the naked eye. It’s not even clear that a spy balloon is more cost-effective than a cluster of small satellites.

But leave aside the military rationale. There are reasons for Chinese military or intelligence agencies to deploy spy balloons that don’t have anything to do with effectiveness, practicality or efficiency. Military decision making doesn’t occur in a vacuum. Especially in a political system as opaque, and undemocratic, as China’s.

It’s entirely possible the balloons are a bad idea that somehow thrived inside the Chinese Communist Party bureaucracy, the same way the U.S. military-industrial-political complex sometimes — some might say often — produces technology that might look great on paper but doesn’t work very well in the real world. Just look at the Navy’s pricey, useless littoral combat ship.

It’s also possible the balloons are working exactlyhow Chinese planners hoped.

Balloons have been used for surveillance systems since the French deployed them to spy on Austrian and Dutch troops in 1794. Yet the advent of aircraft, then satellites rendered balloons obsolete for most military and intelligence applications. After all, an airplane is more maneuverable. A satellite is so high in the sky that it’s impervious to most countermeasures.

While the United States military can still tether static, low-altitude balloons over its frontline outposts, satellites and manned and unmanned spy planes handle most strategic intelligence gathering.

So why did China send free-floating balloons to spy on the United States — at least three times during the administration of Donald Trump and, it seems, twice during President Biden’s term?

It wasn’t for a lack of spacecraft. China oversees more than 500 satellites, making it the world’s second-largest space power, after the United States with its roughly 3,400 satellites. Chinese satellites crisscross the United States every day, snapping photos, scooping up electronic signals and possibly even looking for the telltale infrared bloom resulting from rocket launches on U.S. soil.

The Pentagon knows it’s being watched. Which is why when that 200-foot-tall Chinese spy balloon became big news as it drifted across the United States at an altitude of 60,000 feet last week, the military urged calm.

“We did not assess that it presented a significant collection hazard beyond what already exists in actionable technical means from the Chinese,” Gen. Glen VanHerck told reporters on Monday, two days after the Air Force shot down the balloon off the South Carolina coast. A second device was shot down near Alaska on Friday.

High-altitude balloons might be slightly cheaper than, say, a multimillion-dollar constellation of breadbox-size cubesats, but it’s not clear that the lower cost is worth the obvious visibility and vulnerability of a balloon.

When Kurt Reitinger, a major in the Army, studied surveillance balloons at the Naval Postgraduate School in the early 1990s, he recommended that the military use them only for short missions near U.S. forces. After more than three days, a balloon tends to drift too far off course, he concluded.

Why a major world power wouldn’t deploy a spy balloon is pretty obvious. What’s less obvious is another question. Why, in an era of drones and satellites, would a country as wealthy and powerful as China bother floating spy balloons over the United States? Chinese planners had to know it was only a matter of time before U.S. forces started shooting them down.

Yet it’s important, for any observer of Chinese foreign policy, to remember that an authoritarian regime must do two things to remain in power: project strength abroad while projecting that strength at home.

Authoritarian regimes need external enemies in order to cast themselves as their country’s protector. But the same military provocations that describe the foreign threat are also a subtle reminder to the people back home: Stay in line, lest we aim this weaponry at you.

David Axe is a staff writer at Forbes and the author of several books, most recently, “Drone War: Vietnam.”

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