The only serious explanation I can come up with is that buried in this application is some element of the design which is feasible and which they do want to protect. But even that seems unlikely, given that they could have just made it secret.
Another less likely explanation is that someone in the navy is playing a prank on the public and the patent office. If the person who submitted the application doesn't actually exist, the navy might have trouble tracking down the perpetrator of the hoax.
One final possibility is that it is a recruiting tool. Perhaps by making this public they get a bunch of correspondence from talented individuals who capably point out that is nonsense, or that are capable of doing experiments that demonstrate parts of the patent to be nonfeasible.
What's really odd is the reply of the patent examiner. It's almost like they are asking, "so just to make sure I understand you, this is quite impossible, right?". The military replied, "yeah of course it is, it would require more energy than could be produced by all the power stations on earth, even if the physics were sound. If it makes you feel better, we could add that we are doing this on battery power".
Or the theft of an AWAX by the chinese?
They are not stupid.
When i was at lockheed the chinese were phishing lockheed staff who had attended defense conferences. They managed to get a worm in lockheed that trickle fed them stolen data.
When it was discovered they opened the flood gates and tried to dump mass data out of the lockheed network - which, at the time, only had three egress points to the internet such that lockheed had to shit them down.
Then, lockheed tried to keep an air-gap between vendors they were using... but the chinese hacked the vendors such that they coulld compromise the usb drives being used as the sneakerbet between lockheed and the vendors....
The chinese are not stupid.
The real question is whether they have stupid people making important decisions for them. Or, more stupid than the US has. At least we can be sure that they don't elect them to do it.