[Peter Ward]

I recall when the Drake equation was first mooted, one of the assumptions at the time was most stars didn't even have planets.

That has clearly been proven false.

In our typical human-centric view, it seems the argument has shifted to most planets don't have life, which is a rather bizarre stance, given life grabs a foothold on our own planet in places biologists never came even close to predicting (e.g. in shallow regions around deep ocean volcanic smokers/vents). As humans are very poor at communicating with just about every species on this planet (e.g. dolphins, who have brains as big as ours) it beggars belief we should have much luck chatting with E.T. ...as Sagan was fond of saying "about as much chance as having a conversation with a Petunia".

That said, SETI programs might give us chance of detecting the technology ET uses to chat, without giving any insight to what the chat is about...hence I think are still worthwhile.

The big problem I have is the naivety of humanity. Greg Bear in one of his novels compared us to a child crying in the forest because they are alone...unfortunately crying can attract the wolves.