[dotnet00]

The line I've often heard from defense enthusiasts is that America appears behind on hypersonics because they're aiming for "true" hypersonic weapons, ie ones which are capable of a wide range of navigation while in powered hypersonic flight, as that's what actually makes the concept so potent, by making the missile so fast and unpredictable that current air defense systems would struggle to intercept it.

Without controlled navigable flight, "hypersonics" are much simpler, as you basically just have a ballistic missile, which can still be intercepted by traditional air defense (Russia's Kinzal being an example of this kind of so-called hypersonic missile).