For 18 minutes on one day in April, 15 percent of global internet traffic was rerouted through China, including messages from all four branches of the U.S. military, the Senate, NASA, and several government agencies. A Congressionally appointed commission investigating the incident says state-owned China Telecom might have "hijacked" the traffic to harvest sensitive data. China Telecom calls the allegations "completely groundless." Who's telling the truth? (Watch a Fox News discussion about the controversy)

You'd believe China? It will be hard to conclusively tie this "disturbing" event to the Chinese government or a "patriotic hacker" working for it, says Dean Cheng at the Heritage Foundation. But "when taken in conjunction with other recent Chinese cyber activities," it seems likely this was part of China's increasingly aggressive internet war on the U.S., private enterprise, and its own dissidents.
"Is a U.S.–China battle already underway — in cyberspace?"

Maybe it wasn't malevolent: Internet traffic "accidentally" gets rerouted a few times each year, says Jesus Diaz in Gizmodo, even if not to this extent. Nobody outside of China knows why April's traffic detour happened, but it seems more likely that China was testing its strength as part of the global network than hijacking data for "malicious" reasons.
"China's internet hijacking uncovered"

What about the ongoing risk? Whatever its motives, says McAfee cybersecurity expert Dmitri Alperovitch to NPR, China did corral 15 percent of the world's traffic on that day. Whether it was intentional or not, "the security risk is quite significant" from this sort of rerouting. What's worrisome is that, because of how the internet was set up, there's no easy way to stop it.
"Cybersecurity expert on China net hijacking"