Chinese scientists have become more secretive about their supercomputer development. These machines are essential to improving artificial intelligence, developing vaccines, and predicting hurricanes. But now it’s harder to determine whether China or the U.S. has the fastest supercomputers. WSJ reporter Stu Woo joins host Zoe Thomas to discuss how this happened. Plus, everyday crypto investors are donating their digital currencies to Donald Trump’s presidential campaign. Sign up for the WSJ's free Technology newsletter. Learn more about your ad choices. Visit megaphone.fm/adchoices