Ugh, this is why the term "hypersonics" is misleading. Ballistic missiles ARE hypersonic systems, they travel faster than Mach 5. And that's not just me being p

Ugh, this is why the term "hypersonics" is misleading. Ballistic missiles ARE hypersonic systems, they travel faster than Mach 5. And that's not just me being pedantic. The Kinzhal missile is regularly touted as a "hypersonic" including in this thread. But the Kinzhal is just a ballistic missile, it's actually just an air-launched version of the Iskander. Which interceptor would be used against a target largely comes down to whether the intercept is endo- or exo-atmospheric. The SM3 is an exo-atmospheric intercepter: it's designed to collide with the target in the vacuum of space. The SM6 is an endo-atmospheric interceptor. SM3 can be used against ballistic missiles, including both traditional re-entry vehicles and hypersonic glide vehicles, before they enter the atmosphere. The SM6 can be used against anything in the atmosphere: including ballistic missiles in the terminal descent phase.