The Chinese also imprisoned several other US assets, leaving the agency's Chinese intelligence operations in shambles.

The New York Times is reporting that the Chinese government executed at least a dozen US intelligence agents and sources from 2010-12 thus destroying a network the agency had built over a period of many years.

Daily Caller:

Beijing killed at least a dozen CIA sources and imprisoned several others, former and current U.S. officials told The New York Times. One asset was reportedly shot in front of his coworkers. The systematic campaign largely did away with a CIA espionage network that took the U.S. years to build. Intelligence coming out of China was at its best early in 2010, but by the end of the year, the flow had decreased. By 2011, the CIA realized that their sources were disappearing. “The CIA considers spying in China one of its top priorities, but the country’s extensive security apparatus makes it exceptionally hard for Western spy services to develop sources there,” reports The New York Times, highlighting the significant damage caused by the eradication of intelligence assets. Some officials think a mole tipped the Chinese off, revealing the identities of CIA sources. The FBI and CIA launched an investigation, code-named Honey Badger, into the situation. Investigators suspected a former agency operative who oversaw operations in China and decided to remain in Asia after he left the CIA. The man, a Chinese-American intelligence officer, left the CIA before the leaks began. He had access to the identities of key informants. Other officials who talked to The New York Times suspect that China hacked the covert communications channel. Still others believe that American officers and their sources simply got careless at a time when Chinese spycraft was improving rapidly. By 2013, the CIA had managed to blunt China’s elimination of intelligence assets, although it is unclear how the agency achieved this outcome. China is particularly sensitive to the dangers of foreign espionage, but at the same time, it is highly aggressive in its own spy operations against other countries, especially the U.S. Some Chinese cities pay citizens to hunt foreign spies.

China is not as closed a society as it was in the 1970s and 80s, but make no mistake, the government still exercises iron control over the movement of its citizens and heavily regulates what they see and hear on a daily basis.It's never been easy to penetrate the veil of secrecy under which the Chinese government operates, but apparently, the CIA had enjoyed some success in doing so.

The impact of losing most our inteligence capabilities for several years could be very serious. Although tensions in the South China Sea over the Chinese government's militarization of several man made islands has been out of the news recently, the threat of conflict is ever present. Also, Chinese support for North Korea complicates our strategy in dealing with the nuclear threat.

We aren't totally without eyes and ears in China. Spy satellites and other technological means to gather intelligence are still at our disposal. But there is no substitute for human intelligence - the ability to measure the motives and intent of the Chinese government - and that capability has been temporarily lost.