The point is that in the other two cases (and every other case which has resulted in charges) they HAVE done something more - there is a context to what they have read or written.
Let's assume that there is a real terrorist cell planning a re-run of 7 July. At some stage of their planning the situation if anyone intervenes will be as it is in these cases. Are you
really saying we should be unable to intervene at that stage and have to allow them to run, with all the risks of things not being as we suspect them to be from the imperfect information of our surveillance, until they actually have some explosives or have killed dozens of people (and possibly themselves)?
This case, I acknowledge, appears different than the other two but, so far as I am aware, all that has happened is an
investigation. Are you saying that it is even wrong to
investigate when suspicions exist?