There are absolutely issues of legitimate natural security for many things, then it becomes a matter of how we balance privacy vs. the functional needs of the community.
If the FBI legitimately discovers some crazies trying to make a nuclear bomb, I can imagine a Judge authorizing some kinds of searches which would not otherwise be allowed, and that 'most people' would find that justified.
Of course, widespread surveillance, especially of the arbitrary kind (i.e. catch-alls) and information gathering relegated to local-yocal Police Forces, probably are going to be problematic in the view of 'most people'.
And of course, there is the big hypocritical fact that bothers me a lot about this: that Google, who has absolutely no interest other that 'profit' seems to get a free pass on a lot of things while a national security apparatus, who's objectives are entirely in the realm of 'public service' - even when we don't always agree what those objectives are - are somehow more cynically scrutinized.
So the question is: how much of a threat is Guccifer, and what are reasonable means that we can use to go after him? Which will probably always be a hard question to answer.