I really appreciate your argument, Dong. There was a study I read some time ago, I cannot find it now, which theorized that SETI is critically dangerous to civilization because it is impossible to prevent crafty, malicious aliens from starting something like a suicide cult religion using very convincing messages, no matter how the SETI receiver operators are isolated or restricted in the kinds of messages that they can pass. I think it’s important not to give up on security at all layers but still keep in mind the practical needs of communication.