Regarding your reference to the AGM-183, yes, Trump has a way of spilling the beans. Humorously, the Chinese seem to have heard him, and I do not think this is necessarily a bad thing. My information is that they are now constructing reinforced coastal bunkers to berth their warships. Do you think this costly endeavor might be related to the fact that the USAF has the ability to send their entire shiny 350 ship navy to the bottom of the South China Sea in under four-minutes? War is about economics, and if his slip was accidental, it was brilliantly accidental.
Hypersonic
attackMissile tech has a
long ways to go before it really becomes menacing. So long as they require being placed into a basically ballistic launch profile, their utility is questionable to say the least. Stresses on their airframe when trying to deviate from said ballistic and high speed path of travel just adds to the headaches. (More costly airframes, more weight dedicated to airframe, etc) Which also isn't even getting into the physics of a hypersonic missile operating in thicker atmosphere, more air resistance means more thrust needed to obtain and maintain speed which means either reduced range, or more payload dedicated to fuel rather than explosives, not a great tradeoff. There is some potential of applying some limited stealth profiles to the missiles, but I'd suspect the hypersonic nature of the craft limits the options on that front. (Aerodynamics vs stealth profile is going to be increasingly limited as speed increases, as we again revisit airframe requirements)
Now hypersonic missiles as applied toward
defensive systems are another matter, and we've had those for some time. They're been used in ballistic missile defense systems for over a decade now.
A sufficiently robust ballistic missile defense system renders virtually all of the hypersonic (anti-ship) missile systems rather dubious in their utility. Unless someone manages to blind NORAD, they'll detect the launch, calculate a trajectory, alert the area commands who will then know
where to look for the incoming missile on their own systems. (Assuming they're not already tracking)
The
only thing Hypersonic missiles have going for them is sheer speed, and for the US application for the AGM-183 being air-launched, that speed may increase utility to some degree, but I'm skeptical.
Subsonic missiles, which can terrain follow to avoid RADAR detection, and maneuver with ease(tomahawk's have done so for decades)
and not travel in a straight line have far more battlefield utility and will continue to do so far a long time to come IMO. Further, thanks to being sub-sonic, the airframe requirements for a "stealthier missile" is far less onerous in that application. (Sure NORAD should likely be able to detect their launch as well, but as it doesn't have to travel in a straight line, predicting where its going, and thus where it will be coming from, is a very different ballgame.)
"The Hypersonic missile game" being played out on the internation scene between the US, Russia, China, and the other assorted major powers is those country's blowing large wads of cash to show "we can do it too" in order to field a weapons system that is extremely niche in its utility when going up against another advanced enemy. Perhaps the biggest use the United States will find for the AGM-183 and later missiles of comparable capability is using it to train/test their (anti-ballistic) missile defense systems on how to shoot them down.