There is nothing private about space
There is nothing private about space
So these birds are privately doing things in a public, ahem, space.
Interesting anecdote from one of them (STS-27):
> The day after Atlantis landed, the 1988 Armenian earthquake killed tens of thousands in the Soviet Union. At an astronaut meeting Gibson said, "I know many of you may have been very curious about our classified payload. While I can't go into its design features, I can say Armenia was its first target!" As military astronauts laughed and civilians cringed, Gibson continued, "And we only had the weapon set on stun!"
(Turns out it was actually a synthetic aperture radar recon satellite, not an earthquake machine.)
https://www.livescience.com/x37b-secret-space-plane-facts.ht...
/s