U.S. intelligence shows that China has conducted "human testing" on members of the People's Liberation Army in hopes of developing soldiers with "biologically enhanced capabilities," the nation's top intelligence official said Friday.
Director of National Intelligence John Ratcliffe included that explosive claim in a long Wall Street Journal op-ed in which he made the case that China poses the preeminent national security threat to the U.S.
"There are no ethical boundaries to Beijing's pursuit of power," wrote Ratcliffe, a former Republican congressman from Texas.
His office, and the CIA, did not immediately respond to requests to elaborate on the notion that China sought to create "super soldiers," of the sort depicted in Hollywood films such as Captain America, Bloodshot and Universal Soldier.
Last year, two American scholars wrote a paper examining China's ambitions to apply biotechnology to the battlefield, including what they said were signs that China was interested in using gene-editing technology to enhance human — and perhaps soldier — performance.
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Specifically, the scholars explored Chinese research using the gene-editing tool CRISPR, short for "clusters of regularly interspaced short palindromic repeats." CRISPR has been used to treat genetic diseases and modify plants, but Western scientists consider it unethical to seek to manipulate genes to boost the performance of healthy people.
"While the potential leveraging of CRISPR to increase human capabilities on the future battlefield remains only a hypothetical possibility at the present, there are indications that Chinese military researchers are starting to explore its potential," wrote the scholars, Elsa Kania, an expert on Chinese defense technology at the Center for a New American Security, and Wilson VornDick, a consultant on China matters and former U.S. Navy officer.
"Chinese military scientists and strategists have consistently emphasized that biotechnology could become a 'new strategic commanding heights of the future Revolution in Military Affairs,'" the scholars wrote, quoting a 2015 article in a military newspaper.
One prominent Chinese general, they note, said in 2017 that "modern biotechnology and its integration with information, nano (technology), and the cognitive, etc. domains will have revolutionary influences upon weapons and equipment, the combat spaces, the forms of warfare, and military theories."
VornDick told NBC News in a phone interview he is less concerned about the battlefield advantage such research might provide than about the consequences of tampering with human genes.
"When we start playing around with genetic organisms, there could be unforeseen consequences," he said.
Representatives of the Chinese government did not immediately respond to a request for comment.
The overall message of Ratcliffe's opinion piece is that China is a dangerous adversary that threatens American economic and national security.
"The People's Republic of China poses the greatest threat to America today, and the greatest threat to democracy and freedom world-wide since World War II," he wrote. "The intelligence is clear: Beijing intends to dominate the U.S. and the rest of the planet economically, militarily and technologically."
In an interview with Fox News, Ratcliffe urged President-elect Joe Biden to "be honest" about China.
As NBC News has reported, Biden and his foreign policy advisers agree that China poses a major threat, but they believe the Trump administration offered more bluster than substance in response.