What do we do if SETI is successful?

This is referenced in a sci fi book "The dark forest" of the series "The 3 body problem". It sets a convincing narrative that because of time taken for observation and response and development speed of society it is most likely that all civilizations that announce themselves would likely be a threat in terms of technological supremacy eventually to observing civilizations. In other words, we don't hear anything because any sufficiently advanced civilization would not want to risk being discovered. I.e., the "dark silent forest".

I never did buy the dark forest argument. I mean, even in the books, there were smidgeons of humanity left over. And then all the dimension collapsing strangeness. You just can never be sure.

I dunno, it just reeks of the culture of suspicion in communist China. A product of that place and time.

My own idea is the 'used car salesman' idea of the universe. (Reeking of my own mind and place and time). To me, economics will rule in the galactic community. In that water, metals, energy, it's all cheap and everywhere. No need to have any competition over it. No, the only scarce thing is life and then even more it's intelligence. Any other civilization will be desperate to get rights over us and our history.

So, to me, the aliens will come to us loud and proud. Balloons and banners.

And of course, a contract as long as a the rings of Saturn, with print as small as the atoms.

We shouldn't be wary of the weapons, but the lawyers

I agree, the dark forest argument seems rooted in a kind of paranoia bordering on the insane. No sane culture says “we better just exterminate anyone else we come across just in case,” which is essentially the threat that the dark forest is guarding against. And a culture that does act that way is likely to end up exterminating itself.

The reason for the paranoia is that the risks are maximal. Any planet can destroy any other planet by accelerating a small projectile at it, so long as it achieves sufficient kinetic force. The projectile can be so tiny as to be effectively undetectable until it’s too late. So you have a situation where everyone you meet is carrying WMDs, and you can’t guarantee you’ll be able to get revenge if they fire first. Finally, every actor knows the predicament and nothing else about the other actors. If you don’t know who is on the other side of the radio transmission, but you do know they can destroy you immediately and without consequence, and you know they know you can do the same to them, the only rational choice is to shoot first, because you’d better not shoot second!