OK. Let's say we want to send a signal. Can we produce this same signal ?
Hey, careful, that could be the signal that denotes surplus population available for food!
Sure!
We can send back the same signal.
“Like your planet, ours too is dying due to global warming!”
Probably not now, maybe in the future.
Do we want to send a signal?
The history of man is that every time a higher-tech society meets a lower-tech society, the lower-tech society gets raped. Maybe we should stay inconspicuous until we know how strong we are compared to them.
Right now we are like cave-men compared to any civilization who could travel here.