General Glen VanHerck, the head of North American Aerospace Defense Command, made a stark admission on Monday by revealing that the US had not detected previous flights by Chinese spy balloons over its airspace.
The Air Force officer said the US military had a “domain awareness gap”, in a blunt statement about its failure to detect surveillance balloons that most Americans learned about for the first time last week when an F-22 fighter jet shot one down off the coast of South Carolina.
“We did not detect those threats,” the former fighter pilot said on Monday.
VanHerck was referring to the US military’s failure to detect other Chinese spy balloons — three during the Trump administration and one earlier in the Biden administration — as they entered US airspace. His admission revealed an intelligence failure about China, the prime US rival.
VanHerck said US intelligence had “after the fact . . . assessed those threats from additional means of collection” and informed the Pentagon.
Over the weekend, former Trump administration security officials said they were unaware of Chinese balloons having entered American airspace. Their claims raised questions about what the Pentagon knew more broadly about a Chinese surveillance programme that had received no public attention.
When the Pentagon released the non-classified version of its annual report on the Chinese military in November, for example, the 174-page document made no reference to the spy balloon programme.
One former intelligence official said in the middle of the final year of the Trump administration, senior intelligence officials “generally didn’t know” about the spy balloons. He added that the balloon programme “wouldn’t have been a priority versus more pressing issues” involving China.
It is unclear when the intelligence community discovered the earlier flights. But national security adviser Jake Sullivan on Monday said President Joe Biden had come into office with instructions to boost efforts to detect Chinese espionage.
“We enhanced our capacity to be able to detect things that the Trump administration was unable to detect,” said Sullivan, who added that the administration had looked at “historical patterns” which helped identify previous balloon incidents after they had occurred.
“This may be a situation in which the intelligence community unearthed previously missed evidence from existing databases and/or information from new clandestine sources,” said Dennis Wilder, a former CIA China analyst.
Since shooting down the balloon, the Biden administration has pushed back against criticism that it should have acted earlier.
American officials said the high-altitude balloon — which China claims was a civilian weather balloon — was detected on January 28 when it entered US airspace near the Aleutian Islands in Alaska. Two days later, it flew into Canada before re-entering the US over northern Idaho on Tuesday.
The officials said the balloon was not viewed as a security threat or intelligence risk when it was first detected. But after it entered the continental US on January 31 — and particularly after it flew over a military site in Montana that houses nuclear intercontinental ballistic missiles — the Pentagon took steps to prevent it from obtaining sensitive information.
Biden last Tuesday requested options to shoot down the balloon and was briefed by his commanders the next day. After being told that targeting the balloon over land posed a risk to civilians, he ordered the military to devise a plan to shoot it down over US territorial waters.
Republicans have criticised Biden for letting the balloon fly across the US and spy on military sites. But Sullivan said that gave the military more time to monitor the balloon and learn more about its surveillance capabilities.
“A shootdown over water would create a greater possibility that we could effectively exploit the wreckage than if it were shot down over land,” he added.
Some experts have asked why China would fly a balloon around the world to spy on the US when it has satellites that provide high-resolution images. But several former intelligence officials said it could have other functions, such as intercepting communications that are hard to obtain from space.
One former intelligence official said the “main function” may not have been to capture imagery. “China can employ multiple kinds of sensors depending on the mission,” he said, referring to things such as signals intelligence.
Another former intelligence official said the balloon may have been doing “tip and cue” operations. In this case, the balloon detects something of interest — such as conversations or electronic signals — and sends the co-ordinates to satellites, which focus their higher-end capabilities on the targeted location.
Others have suggested the balloon may have been triggering radar defences to learn more about how US weapon systems communicate with each other.
VanHerck declined to say what the US had gleaned about the balloon during its flight but said it gave the military the opportunity to assess things such as its ability to transmit information back to China.
“You will see in the future that timeframe was well worth its value,” he said.
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