At a congressional US-China Economic and Security Review Commission hearing last week, experts claimed that Chinese spying currently poses the most significant threat to US security.
Many of those apprehended were involved in the theft of trade secrets and technology useful to the Chinese military, including Wenxia Man, who was convicted last week of attempting to illegally acquire and export to China fighter-jet engines and an unmanned aerial vehicle.
An undercover agent discovered that Man's buyer in China was a technology spy working for that country's military, and intended to back-engineer and replicate foreign defense items purchased abroad.
"The PRC today is the most aggressive intelligence threat facing the United States," Major said, adding that Beijing's combined use of cyberattacks and sophisticated spying aggravates the problem.
"FBI investigations and arrests for industrial espionage and violations of export control laws are at an all-time high, predominately linked to the Chinese government," said Michele Van Cleave, former US National Counterintelligence Executive, a senior government counterspy post.
Analysts believe that China's recent strategic nuclear forces buildup is, to a large extent, due to the theft of US nuclear secrets, both through the recruitment of agents and the use of online espionage.