A Kinzhal missile is not what people are referring to when they talk about "hypersonic missiles". They're usually referring to either maneuverable glide vehicle

A Kinzhal missile is not what people are referring to when they talk about "hypersonic missiles". They're usually referring to either maneuverable glide vehicles (lifting bodies for warheads that allow them to change course during the terminal phase), or air-breathing SCAMJETs cruise missiles that are both maneuverable and can fly at low altitude to avoid detection (well, other than the noise). Also consider that russia's Kinzhal can go about mach 4-5. That sounds pretty bad, until you realize that good old ICBMs re-enter from space and travel in atmosphere somewhere between mach 15 and 20. Fast missiles like Kinzhal are not new at all. As far back as the 60s the USA had the Sprint and Nike which could accelerate from the ground to mach 10 in seconds and would glow white hot from heating. Even maneuverable glide vehicles aren't new, the Pershing II could perform limited course changes during descent back in the early 80s. Yes, fast missiles are scary, but they're not in the same class as true air-breathing hypersonic weapons. https://en.wikipedia.org/wiki/Nike_Zeus https://en.wikipedia.org/wiki/Nike_Zeus https://en.wikipedia.org/wiki/Sprint_(missile) https://en.wikipedia.org/wiki/Sprint_(missile) https://en.wikipedia.org/wiki/Pershing_II https://en.wikipedia.org/wiki/Pershing_II