(Bloomberg) -- Unusually for high-altitude balloons, the Chinese one shot down by the US Air Force in February flew low enough to be seen from the ground. That turned it into a rare, in-your-face symbol for what US officials call an increasingly aggressive, years-long spying campaign by China around the globe. Under President Xi Jinping, China has poured hundreds of billions of dollars into upgrading its military, from nuclear missiles to hypersonic glide vehicles. That apparently includes investing in the so-called near-space arena to improve surveillance capabilities as well. 

1. What do we know about China’s alleged spy balloon?

Officials in China said the airship — whose payload was similar in size to a regional jet — was a civilian weather balloon that blew off course. US President Joe Biden said it was “gathering information over America.” High-resolution imagery provided by U-2 spy planes that flew past the balloon revealed an array of surveillance equipment capable of collecting communications signals, according to a State Department official. The balloon traveled over sensitive military sites and had a small motor and propellers, indicating that it was maneuverable. (According to the Pentagon, US officials took steps — which weren’t detailed — “to protect against the balloon’s collection of sensitive information.”) After a week during which it traversed North America, a US Air Force F-22 Raptor fighter shot it down on Feb. 4 off the South Carolina coast. Navy and Coast Guard personnel were sent to recover the debris in relatively shallow waters a few miles offshore. In the days after, several other airborne objects were shot down, though it wasn’t clear what they were. On Feb. 16, Biden said there was no evidence that they were tied to the balloon incident and were likely connected to commercial or research ventures. 

2. Why use balloons?

Cheap, quiet and hard to reach, balloons have long been used for reconnaissance, including during the US Civil War. Today, balloons have limited ability to collect meaningful data beyond what the Chinese can already gather through their satellite network, US officials have told Bloomberg News. Still, they are able to photograph facilities from different angles and linger for longer over areas than satellites, providing a possible advantages. They can also be deployed unexpectedly – so the US has less time to hide assets they are hoping to keep secret – and often have infrared sensors that provide different information than satellites. The New York Times reported that People’s Liberation Army Daily, the main newspaper of the Chinese military, published an article as early as 2020 describing how near space “has become a new battleground in modern warfare” and has repeatedly urged officers to take balloons seriously. It also said Chinese military scientists have worked on new materials, designs and navigation tools to make them more durable, harder to detect or even to serve as weapons platforms.

3. What other kinds of espionage does China conduct in the US?

The US and its allies have accused China of increasing the scale of spying and influence operations — including the hacking of Microsoft Corp.’s Exchange email servers in 2021 — and of using spies, scholars, company insiders and front companies to gain access to cutting-edge technology and research. The US State Department ordered the Chinese consulate in Houston, America’s energy capital, to close in 2020 after two Chinese citizens were convicted of trying to steal trade secrets. A former Harvard University chemical biology professor was convicted in 2021 in connection with hiding ties to a Chinese-run recruitment program. Biden has maintained a proclamation by his predecessor, Donald Trump, barring visas for thousands of post-graduate students and researchers deemed to have ties with China’s military schools.

4. What does China say?

China has called such espionage charges slanderous and has long insisted that it’s a victim, not a perpetrator, of cyberattacks as well as aggressive behavior by the US and other adversaries. A Foreign Ministry spokesman said in February that US balloons have flown “illegally” over China more than 10 times since early 2022. China has long complained about US surveillance by ships and spy planes near its territory, leading to occasional confrontations. It has said the US is “the world’s number one country of spying, eavesdropping and surveillance, that is plainly visible to the international community.”

5. Who coordinates Chinese intelligence?

China’s main intelligence agency is the Ministry of State Security, established in 1983. Compared with the US, it’s something of a mashup: It conducts intelligence operations abroad like the Central Intelligence Agency, counterespionage at home like the Federal Bureau of Investigation and cyber-snooping like the National Security Agency. The number of employees is classified, as is the exact location of MSS headquarters, said to be a nondescript building in western Beijing. It has no public website or press office. Its former boss, Chen Wenqing, was promoted to the Politburo and the Central Secretariat in October, the first chief spy to make it to the Communist Party’s inner political circle since the ministry was established in the early 1980s.

6. How good is China’s espionage?

Hard to know. The New York Times reported in 2018 that Chinese (and Russian) intelligence monitored Trump’s calls on unsecured cellular devices. Trump called the report incorrect. In 2017, the Times reported that Chinese authorities had dismantled CIA operations in China over several years, killing at least a dozen of the agency’s sources in what US officials called one of their worst intelligence breaches in decades. Australian outlets Fairfax Media/Nine News reported that the MSS was responsible for a wave of attacks on Australian companies in 2018, despite a bilateral agreement not to steal each other’s commercial secrets. A senior MSS officer, Yanjun Xu, was sentenced to 20 years in a US prison last year for attempting to steal trade secrets from Western aerospace companies. He was the first Chinese spy to be extradited to the US to face charges, after his arrest in Belgium.

7. How worried is the US?

The annual threat assessment by the Office of the Director of National Intelligence last year listed China first in a list of challengers that also included Russia, Iran and North Korea. It warned about China’s growing military power, including its nuclear arsenal, and called the country the “top threat” to US technological competitiveness and “the broadest, most active, and persistent cyber espionage threat” to government and private sector networks. The US National Counter intelligence and Security Center developed new guidance for academic institutions to help them to protect their “crown jewels” from Chinese and other spies. Meanwhile, the US is working on its own high-altitude inflatables to add to an already extensive surveillance network, Politico reported last year, citing Pentagon budget documents.

8. Where else are aircraft being spotted?

The Chinese balloon was part of a military-led spy program that spanned more than 40 countries, Biden administration officials said. General Glen VanHerck, head of the North American Aerospace Defense Command, has said that Norad had failed to detect balloons that flew near US bases during the Trump presidency and later learned about them from the US intelligence community. NATO Secretary General Jens Stoltenberg said China over the last few years “has invested heavily in new military capabilities, including different types of surveillance,” including in Europe. In Taiwan last year, a balloon was reported to have hovered for hours over the Taipei’s Songshan Airport, which is also used by the military. Japanese media have reported at least two similar-looking balloons floating over the country since 2020. Chinese Foreign Ministry spokeswoman Mao Ning told reporters on Feb. 6 that a balloon that the Pentagon spotted over Latin America had, like the US one, been blown off course. She said China follows international law, adding that “we will not pose any threat to any country.” 

--With assistance from Peter Martin, Tony Capaccio, Karen Leigh and Low De Wei.

(Updates with Biden comment on other objects in question 1)

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