Don't get too hung up on the name. They're two different things. Yes, ICBMs also travel at hypersonic speeds, but this is only because they have no atmospheric friction slowing them down. ICBM's trajectory takes them hundreds of miles into space. In atmosphere they're much slower.
Hypersonics travel at many multiples of the speed of sound in atmosphere using boost glide or scramjet. Without having to leave and re-enter the atmosphere they can hit their target much faster and theorhetically fly below defeat systems.
Read the other comments. German WW2 V-2 rockets were hypersonic, and no, ICBMs are not "slow" in the atmosphere.
The other comments are just flat wrong.
V2s went 3400 mph. That's short of mach 5 which is hypersonic minimum. Hypersonics are vastly faster then mach 5 with way more precession than any rocket. . ICBMs achieve their speed entirely based off of their fullburn which forces them into space. They couldn't do that in atmosphere. If you give them their full burn they're leaving. If you didn't you're not getting their full speed or having any precission.
Like I said. You're too hung up on the name. Things can travel at hypersonic speeds without being what we classify as hypersonic weapons.
No, hypersonics of today are faster in their middle phase, just like ICBMs. They still slow down before impact.
You are spreading DOD FUD.
Read and watch:
https://spectrum.ieee.org/hypersonic-missiles-are-being-hyped
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