I mean, our X-15 was a manned hypersonic aircraft (by a good margin of the minimum 5x speed) in the 1960's, and ICBM's have been guided unmanned long range hype

I mean, our X-15 was a manned hypersonic aircraft (by a good margin of the minimum 5x speed) in the 1960's, and ICBM's have been guided unmanned long range hypersonic munitions since a similar era, just to name a few. We have plenty of experience with hypersonics, and we almost certainly have continued research and experimentation into the field. The real technological linchpin isn't so much the speed, but would be things like guidance, precision and manuevering at those speeds, or perhaps other things like stealth, heat management materials (lot of friction from the air when you're ripping through it at those speeds), transatmospheric flight, advancements in hybrid (sc)ramjet engines, etc. Going hypersonic in and of itself is nothing new. We've been doing that since the 60's. Shit we made a manhole cover go hypersonic before the Russian's ever launched sputnik. It's what something can do after its moving at hypersonic speed that's of real consequence.