We can't be sure what the take in the films is going to be, but just looking at the basic JL mythos... No. It is in no way absurd from an in-story point of view to see that the League could operate totally independent of any and all governments.
It's fairly absurd. That's why DC did away with it.
Bruce Wayne? Billionaire.
Being a billionaire doesn't mean you can build a satellite, Bill Gates at his richest couldn't have built the ISS. Bruce could potentially afford one if he were the richest man in the world, but people still need to build it.
Ollie Queen? Billionaire.
Also doesn't exist in this universe.
Diana of Paradise Isle? Crown Princess of a people that date back to BEFORE the classical Greek era.
Last time I checked neither the Amazons nor the ancient Greeks were big on space travel.
Arthur Curry/Orin? King of legendary Atlantis.
Last time I checked the Atlanteans also weren't overly concerned with space travel.
Those individuals alone bring enormous financial resources (want to guess that the royal coffers of Atlantis and the Amazons DWARFS Ollie and Bruce's personal wealth? Cuz they would).
Oh yes, because two species who have spent millennia actively distancing themselves from humans, actively despise them and exile their human representatives (both Diana and Orin) are going to spend vast quantities on defending humanity from itself.
Anyway, getting money from the royal families of Themyscira or Atlantis would be [BLACKOUT]funding from a government.[/BLACKOUT]
Then there are those that bring other worldly power or alien tech or both to the table like Superman, Flash, GL or J'onn.
Superman has no alien tech.
Flash's power would extend to being able to do things very fast.
GL doesn't exist yet (at least not one who'd be in the JL)
J'onn doesn't exist.
The real cost of the ISS was just in getting it up there, which would be a cinch for many a Leaguer by themselves much less with a little help from someone with powers too. With Superman, GL, Flash, J'onn and Wonder Woman doing the heavy lifting of construction and assembling, such a task would take far less time and money than if some government entity were to do the same. Pooling the talents and resources of the League seems to me, to be the most obvious answer to the Watchtower's existence, and lo and behold, the satellite's justification has ALWAYS been thus.
Actually, only one third of the cost of the ISS cost was getting it in space. That's still $100 billion for construction. As for assembly, I find it absurd that a farmer, an anachronistic warrior, and a cop could manufacture and produce and assemble a huge, fully functional space station. There's a reason we use specialists to design this stuff, and why it takes them years.
Anyway, how would Batman, Cyborg, and Flash get up there? As far as we know, there's no Green Lantern to get them there.
inb4 teleporter
It's ridiculous to think that Kryptonians can't develop teleportation technology to go from low planetary orbit to planet surface, but humans can.
Also bee-tee-dubs, it's been a while since the Justice League were self funded.
As for us knowing about the construction of the it... Yeah, we would know. I think that would be the point, and as shown in the CADMUS story on JLU, opens up the canvas on which to tell stories if you go with what the reaction to such a group with an orbiting fortress in space would be here on Earth.
That's not the issue. People would know anyway, it'd be visible in the night sky to the naked eye.
I see this point of view more and more these days, and it baffles me when you take the full range of what these fantastical individuals can do seriously. And that's important to note. The fantasy and the practical "realism" can live side by side in these films and still be both "grounded" and "fantastic".
Yeah, they can. But a skyscraper sized satellite (ie the most expensive thing that would have ever been built) is different to other things, like Clark Kent's glasses or who pumps the Batmobile's tyres.
Even if Bruce were made as rich as Bill Gates was at his richest (over $100 billion), don't you think people would notice if he sank every penny of his personal fortune into..... nothing? But still employed hundreds of people on this non-existent project? If $100 billion disappeared from the face of the Earth?