I’ve been hearing about these hypersonic jets since the Reagan administration - lots of talk, no action. I was a teenager when President Reagan talked about a new Orient Express, capable of flying from Washington to Tokyo in 2 hours - I expect I’ll be dead of old age before any such thing is ever built. The early 20th century’s pace of technological innovation is over.
It took aviation more than fifty years from Kitty Hawk to when jet airliners made passenger travel by air safe, cheap, comfortable, and routine. All the while the promise of such development was touted as if it was on the verge of realization. As a practical matter, such hype is part of the effort to draw attention, resources, and support, with many wrong turns and failed ideas along the way. Who knows, but an “Orient Express” may one day emerge as part of a system of rocket-powered airliners, depending on technology and cost considerations.
Large scale war is a great motivation for technological progress. Sadly, nukes mean that major wars between major powers don’t exist to drive the urgency and momentum behind technological progress.