A hypersonic Zircon cruise missile is fired from the Russian guided missile frigate 'Admiral Gorshkov' during a test in the Barents Sea on May 28, 2022.  Russian Defence Ministry
A hypersonic Zircon cruise missile is fired from the Russian guided missile frigate 'Admiral Gorshkov' during a test in the Barents Sea on May 28, 2022. Russian Defence Ministry

What is a hypersonic missile and which countries say they have them?