>>715379103
The nearest exoplanet from us is 4 light years away meaning it takes 4 years to send a message and another 4 to receive

How many light years would you deem is too much that you would label interacting with them to be impractical, that number will be the "search radius" for the Aliens

Take into account that the milky was galaxy is 100,000 light years from end to end, and the distance to the next galaxy is 2.537 million light years

So my bet is there are none in our "search radius" if it takes 4 years just to send a message to the nearest rock that has no life in it, but let's just agree to disagree if your number is higher

>>715379541
>mobilization of security resources

Star Trek type aliens aren't real