> Magazine depths will be so limited that they'll only be used for the highest priority targets. They won't be enough to end any major conflict by themselves.

I'm probably being incredibly naive in saying this, but what about "non-wartime" decapitation strikes — where instead of going to war, you just lob some well-timed hypersonic missiles at your enemy's capitol building / parliament / etc. while all key players are inside; presumably not as a way to leave the enemy nation leaderless, but rather to aid an insurgent faction that favors you to take advantage of the chaos to grab power? I.e., why doesn't the CIA bring ICBMs along to their staged coups?

If you do this, the enemy's nuclear-weapons services will look in the playbook under "what to do if someone kills the government", see, "launch everything as a counterattack", and press the button.

A key advantage of a hypersonic weapon is the possibility of first-strikes to disable the enemy's retaliation systems before they have the ability to launch more-traditional retaliatory responses. Only submarines are likely to be mostly-immune to them.

Sure that type of decapitation strike might be attempted on occasion against weaker countries. The US basically tried to take out Saddam Hussein and his inner circle using precision strikes at the beginning of the 2003 Iraq invasion but they mostly missed.

So why are the Chinese doing it?

https://www.heritage.org/asia/commentary/chinas-new-weapon-j...

The Chinese weapon is ground launched, exactly as I stated. Sure you can boost such a weapon up above most of the atmosphere in order to get longer range, but the downside is that higher altitude flight paths make it easier to detect and counter.

AFAIK, there are no publicized counters to partially orbital hypersonic glide weapons in their glide phase due to their maneuverability and speed. Perhaps THAAD - but it may be difficult to ascertain the target when a weapon can glide halfway across the world

Well in theory the RIM-174 (SM-6) has some limited ability to intercept hypersonic glide weapons. Although obviously that's never been tested.

There are counters to hypersonic glide weapons beyond shooting them down. If you can detect it early enough then the target ship can change course and try to evade. The sensors on those missiles have very limited field of view so if it's not receiving a real time target track data link for course correction then it can be possibly be dodged (depending on how many are incoming, weather, and other factors). Even if the target can't evade, a bit of advance warning would at least allow for cueing EW countermeasures.

Nah? You don't put cruise missiles in space. You put mass in space.

I supposed the point would be to hit the highest priority targets and nothing else. Loss of command and logistics has a profound effect on endurance

Putting mass in space as a weapon is just a silly scifi idea disconnected from reality. Even with modern reusable rockets, launch costs are still extremely high, especially if you need enough platforms to hit time sensitive targets. And the platforms wouldn't be survivable. There are cheaper, more effective ways to fulfill the mission.

Not to mention that you get at most as much kinetic energy out as you put in, minus losses to atmospheric drag and what's needed to drop the orbit (you have to burn retrograde to return from orbit).