Let's wait and see the evidence (if any) that the balloon's altitude and track are being controlled remotely, shall we ?

Occam and I aren't holding our breath ...

A couple cell phones perhaps?

having been partially involved in some high-altitude un-manned ballooning from the UK I have a few thoughts.

From the pictures that I have seen of the balloon and its payload there does not appear to be a parachute - there might be one packed inside somewhere, but we don't know that. If the balloon is shot and ripped/torn then the payload will come down rapidly; technically, it will 'plummet', then 'terminal velocity', and finally 'unscheduled disassembly on the ground'. At which point the Intell community will have lost much of there chance to examine it for information. They will be able to gather some info the smashed remains, but not nearly as much as they could from the intact payload (assuming it isn't booby-trapped!).
There are a couple of scenarios to consider -
- let it continue floating slowly across the entire USA, and when it gets close to the eastern shore of southern shore, then you attempt to bring it down, such that it lands in the sea. It would still be a destructive landing, but it won't cause any harm to land, property or people.
- attempt to introduce a very small hole in the envelope of the balloon, such that the lifting-gas is lost gradually, and the balloon descends gradually. It is still uncontrolled in which direction it is going, and it is going to cause quite some chaos in the US airspace, but it will come down eventually ... hopefully not in/on a major population centre, but cannot be guaranteed. The problem with this is that to introduce a tiny hole in the envelope is extremely difficult ... a pin-prick becomes a small hole, which becomes a small tear and then a large tear, which leads to the 'sudden plummet' outcome.
What the Intell people want is for it to descend gradually and gently alight in a field in the middle of nowhere ... the payload suspended underneath is not too damaged, and then allows extensive analysis of whatever is on board. If it does land in a built-up area then recovery might be a bit more of a problem, but still 'doable'. It also might land in the top of trees in a forest, which is not ideal.

If we were to assume that it was taking pictures of whatever it flies over, it is a trivial task to to convert those pics to a digital format and transmit them to a ground station (hell, amateurs and enthusiasts have been doing it for years ...) and it is theoretically possible for those same images to be transmitted upwards to a passing satellite for storage and later download when over China. But that's what the intell people will be able to tell if they get theirs hands on a complete payload.

It is possible that the balloon knows exactly where it is because of GPS. Could they switch-off GPS for a short while to see if it confuses the entire thing? Could they GPS-spoof to make the balloon think that it was back over Chinese territory and see it it has a "I'm home, I will descend to land" system?

I suspect that the scenario where one of their balloons continues circumnavigating the earth to return to its launch point probably hasn't occurred to the Chinese.

Well, you only asked how not if.

I didn't say it was being controlled.

Well, despite your skepticism, free balloons are controllable to some extent. The U.S. Balloon Fiesta features free gas balloon races for distance ala the Coupe Aéronatique Gordon Bennett, in which gas balloons are controlled by altering altitude to pick up suitable winds. A remotely controlled free gas balloon is certainly possible; the Chinese do state their machine is partially controlled as to direction.

https://balloonfiesta.com/Americas-Challenge

A photo on twitter shows that it has been neutralised.

Reportedly shot down (it will be interesting to see how and by what) such that it came down off the east coast.

F-22 with a AIM-9 .Pilot gets to put a balloon on the aircraft.

Serious question but, would a missle even explode if it hit a balloon? Or did it just tear through it like tissue paper?

Seems like an expensive method to kill a balloon. Cost of an AIM-9 compared to a weather balloon... maybe I'm wrong there.

Imagine if the Raptor pilot missed the shot! I’d hate to be the F-22 Pilot who missed a balloon! Imagine the ribbing he’d get for the rest of his career!

So as our friendly Asian paradigmatic Communist regime's inadvertently, accidentally, and innocently misguided high-altitude balloon drifted its way across - if I'm getting the picture here - the Aleutian Islands, Alaska and Canada, and traipsing the airspace above Montana .... this situation might, I'm just saying it might, have been worthy of reference in somebody's NOTAMs. Yes? - I mean, it was an event with potential effects, potentially serious, on air-missions, was it not??

Oh that's right. The NOTAM system had a hiccup, a glitch. A contractor employed by FAA didn't perform a task or tasks correctly, and she-bang, thud, the system conked out. Occam is impressed.

I'm sure there's no need here (insert tone of Joe Pesci getting Marissa Tomei to look more closely at the tire tracks photo.... )..... as I was saying, I'm sure there's no need to ask questions like -
what were the qualifications of the contractor who is blamed?, what were the credentials? Had this contractor - the individual(s) or corporate entity or both - had a good performance record until this event? How often were these "data files" worked on? And so forth. It sounds too simple to be true. And especially, what about Canada's nearly simultaneous glitch, I ask??

I'm not theorizing anything. I simply do not give credence to the official explanation, so far, of what happened to the NOTAM system in Uncle Sam's offices and up in Maple Flags country. And then a very, Very, VERY NOTAM-worthy event happens, but it's not widely noted to Air-Missions? [Correction - it was noted - thank you India Four Two] Okay, OK, I'll just go back to work now.... on my 2023 edition of Letter from WR to Santa Claus, a wish-list longer than ever.

Yes - a NOTAM is required for aircraft at an altitude no one but a select few military can reach. There's also one for the International Space Station. /s

Willow Run,

I draw your attention to this NOTAM for the Edmonton FIR up in Maple Flags and Santa Claus country. ;)
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https://cimg4.ibsrv.net/gimg/pprune....d30385e8fc.png
https://cimg6.ibsrv.net/gimg/pprune....a21aa95d56.png

Canadians, eh? There was a US NOTAM to close airspace on the East coast but that was just ahead of the military shoot-down.

Of course the Chinese have cried foul after having not gotten overflight permission in the first place.

Dear Willow, do not want to sound pedantic , but there is no conspiracy theory here regarding the NOTAMs, First above 60.000ft is non-regulatoryairspace and the FAA is not responsible for airspace above that ,Secondly NOTAMs are by(ICAO) definition to warn about things affecting CIVIL flight operations ,. Since Concorde is gone , there are no more civil operations above 60.000ft ., so also no NOTAM required.

The Canadian NOTAM posted here by by India Four Two is indicating a volume of application between 20.000 ft and 45.000 ft .so it might or might not even refer to this perticular balloon , but if it is, it make sense as they could think it could come down on this perticular piece of airspace, . The US had obviously made anothere ertimation: i.e. that it would just cruise and follow the jetstream at 65.000 ft..so again no need for a NOTAM

In my active time as Controller in the ( upper ) airspace I controlled . I saw regularly NOTAMS referring to weather balloon launches , but as a warning when they go up, slowly and from Surface to 45.000 ft ( our controlled airspace limit in my FIR) but I never saw one on the cruise part , and neither on coming down as nobodyreally knows when and where they will come down., (except thoses that have a self destruct mechanism )

My guess on all this, is that it is indeed a surveillance balloon that should never have gone that far up for some reason , got into the jetstream and could not be controlled out ( up far North the jetstream goes well above 100 Kts) someone in China decided to let it go and see what the US reaction will be, Well they know now.,The path and fate of the second similar balloon now over Central America and the Carribbean , if it is is the same type, and launched from the same place in China, would perhaps be a good indication of what was initially intended and if something went wrong. ,

As to get the debris back from the sea, well normally everthing in weather balloons is made of extremely light material to save weight,,if the strucure is attached to something heavy, like a camera or a large transmitter , the terminal velocity of the whole thing when dropping from 65.000ft would be so high when hitting the water and not easy to get those small debris back. If the whole thing is made of very light material and comes down slowly ,them the area to search will be huge...In both cases it could take quite a while to get everthing back I would say .

It would have been a gun run and not a missile they would have used.

BBC reports that a sidewinder missile was used

Time to change the thread title (and the offense), from Loitering to Littering, methinks.