There is a competition running at the moment, sponsored by a technology billionaire in the States, to come up with the best possible message to broadcast out into the cosmos to possible alien civilisations. The prize for the winning message is $1m and a British group of scientists are amongst those competing. Interestingly, this team all agree that writing such a message is important, but they are split over the question of whether, once written, the message should actually be sent. What, for example, if we get the attention of a civilisation very different to ours and they decide to come and pay a hostile call (goes the thinking against).
The question I would ask these people is “What result do you hope to achieve from sending the message?”