Videos Russia and China are ahead of the US in developing and testing hypersonic missile technology, especially when it comes to building wind tunnels. CNN’s Kristin Fisher has the details. #CNN #News Articles You May Like ‘Living my worst nightmare’, says mother of Daejaun Campbell – killed in machete attack Diddy’s family leaves court after sentencing Prince William aiming for change with Earthshot Prize ‘Very nice gentleman’: Trump forgets House minority leader’s name