However, what if we encounter intelligent life, similar to humans, on another planet? Do we plan to coexist with them, colonize them, or worse, wipe them out? What is our strategy if we meet them?
We cannot even accurately estimate how long any given life form has existed.
For example, Earth is relatively young planet, and exists planets which are Billion years older.
And according to Turing theorem, we could only understand life form similarly developed or less developed than our.
So, if we will encounter similarly developed or less developed life form (younger than our), we could make decision what to do with it.
But if we will encounter much older life form, I think limit is just about few hundred years difference, we just will not understand them, may be even they will look like natural phenomena or super-natural as gods.
And when we will encounter less developed ETs, we cannot be sure, that nearby not hidden much more developed ETs, which could wipe us. So I think, safest for us will be to avoid any interaction and research them with remote sense technologies.
Vs. if we've technically "encountered" them, but it takes (say) 100 years and $1B per person to travel in between? Only the most fanatical - who probably can't afford the time, nor ticket price - might support any policy except peaceful coexistence.
We struggle to get along with ourselves. We struggle to visit the moon. We can't even survive in a controlled simulation of another planet. We are already dying out in reference to replacement rates in most countries workers and consumers vs retired etc... It is not even clear that we are anywhere near passing the phase of wars with one another.
If another species exists that manages to get all the way here the decision regarding what happens will be entirely up to them in my opinion.
Some day, there will be those who comprehend civilizing accord, without which we will only know savage power.
Btw, they’re already here and they can hear you think!