> I am not entirely convinced. Was not Hubble damaged and got an upgrade lateron?

It was made wrong (the mirror was shaped incorrectly).

Luckily the HST was designed to be serviced (it had components within it that would degrade over time, and some components could realistically be upgraded as technology became better), so they swapped out the optics so that it worked with the incorrectly shaped mirror.

---

> I don't think the USA could keep mega-super-duper technology hidden from others in the long run.

The only things being hidden are basically trade secret stuff, e.g. better materials, better software, better sensors, etc...

The US had a geopolitical advantage keeping their sensor tech secret. Other nations didn't know how good they were and only hid their actions to the degree they thought shielded themselves. When the knowledge eventually came out, other nations knew if they wanted their sercets kept, they would have to invest in better obfuscation.

---

> And NASA often wants more money - just take the whole search for life on planets. This is so pointless - life exists already here. What is the addiction to want to find life outside of the planet? Other than, of course, getting more money, which is understandable, but it doesn't answer the question.

Since you're not behind the rationale of curiosity, I'll present you with a utilitarian justification:

Ancient Rome had steam power (see: Aeolipile). But it was basically seen as a useless toy. It took almost 2 millennia until the Industrial Revolution happened and steam power took its rightful place in our history. Humanity got there, but it took a lot longer than it needed to.

Imagine what would have happened instead if Ancient Rome could have looked across an ocean and seen a civilisation harnessing steam power to its fullest. It would not have taken almost 2 millennia for them to catch up. They just needed a hint as to where to focus their attention.

History is littered with missed paths that could have accelerated our progress.

Newton was playing around with shaped glass and investigating optics. What if he heard of someone else seeing weird lines when they left their prism in the sun? He had everything he needed to stumble upon the ultraviolet catastrophe himself and we would have ended up with quantum mechanics centuries earlier.

Going back further, what if the Antikythera Mechanism's gearwork technology became widespread? What if the ancients had their own Babbage and created programming millennia before?

Penicillin could have been discovered even earlier.

All that's needed is a little observation of "Huh, that's weird" and everything spills out of that.

Investigating a line of inquiry doesn't guarantee that we're going to end up with something. So we have to investigate wide, rather than deep.

But imagine if we find an alien civilisation and make another "Huh, that's weird" observation. All of a sudden we have a higher confidence that an investigation down a specific path does lead to something new.

- An exoplanet not moving elliptically or hyperbolically? That'd focus a large amount of attention into overcoming previous assumptions about inertia.

- Lot of lensing effects and bursts of shifted light? That'd focus a large amount of attention into bending space.

- Seeing spectral lines that don't match known matter? That'd focus a large amount of attention into the strong nuclear force, exotic matter, magmatter, etc...

- An impossible star? That'd focus a large amount of attention into the processes powering that star.

- etc...

TL;DR: Finding another civilisation doing something basically changes the rate of return calculation for research.