The Chinese government has never exported, nor even tried to export, its J-20 stealth fighter. There’s one major reason why.

In the years immediately following the Chengdu-built J-20’s 2011 debut, Western analysts assumed the large, angular, twin-engine fighter would, like most Chinese weapons, become an export commodity.

Instead, Beijing decided to keep the J-20’s high-end military capabilities all to itself. Cash isn’t worth giving up the radar-evading warplane’s secrets, in the Chinese government’s estimation.

Not coincidentally, the United States adopted a similar policy regarding its own F-22 stealth fighter.

Song Zhongping, a former officer in Beijing’s strategic missile force, revealed the export ban in a December 2014 interview with China’s Phoenix T.V. news program.

“The export of advanced Chinese military technology is prohibited,” Song said. “This is in order to keep J-20’s fifth-generation technology out of hostile hands.”

That’s the same rationale the U.S. Congress cited when it formally outlawed sales of the F-22 stealth fighter in the mid-2000s. Prior to that, Japan had asked to acquire F-22s.

But Tokyo has been an occasionally unreliable friend to the U.S. when it comes to secret technology. In 2007, Japanese authorities caught a Japanese navy petty officer apparently trying to pass to China information on the U.S.-made Aegis radar.

What’s ironic about China’s J-20 sales-restriction is that many observers strongly suspect Beijing’s engineers derived the plane’s design in part from data that Chinese hackers have stolen from the American-led F-35 stealth fighter program.

The U.S. expressly designed the F-35 to be safely exportable. The F-35 is smaller, slower and less stealthy than the F-22 is. But it still includes sensitive technologies including sophisticated sensors and radar-absorbing coatings.

In any event, Song described the J-20 restriction as directly connected to the F-22 prohibition. “If one day the United States decides to export the F-22, China might consider lifting its ban, as well,” he said.

His reasoning seems to be that if America’s allies possessed F-22s, China’s allies would need J-20s to balance them. And with the F-22 proliferating, its secrets would proliferate, too — obviating any need to similarly limit the spread of the J-20’s presumably similar technology.

The J-20 export-ban doesn’t mean China is giving up on the lucrative global market for radar-evading warplanes. Shortly after the J-20’s debut, the rival Shenyang Aircraft Corporation unveiled its smaller FC-31 stealth-fighter prototype.

Unlike the government-sponsored J-20, the FC-31 is strictly a private venture that Shenyang intends to sell abroad. So far there have been no takers.

The FC-31 represents Beijing’s opportunity to compete in the lucrative world market for radar-evading fighters. If the sensitive J-20 is like America’s F-22, then the commoditized FC-31 is analogous to the U.S. F-35.

The Chinese air force began receiving copies of the J-20 for front-line use back in 2017 — 12 years after the F-22 entered service. By late 2019 there were at least 13 J-20s in service. The air force has focused its efforts on replacing the fighter’s Russian AL-31 engines with custom-made WS-10s.

David Axe serves as Defense Editor of the National Interest. He is the author of the graphic novels  War Fix, War Is Boring and Machete Squad.