I haven't been able to satisfy any clear conditions for being good or
   bad guys. Not even for being patriots or not.
   Ultimately it doesn't matter. Their jobs are inherently evil. Spying
   always has been, but this is different because it involves everyone
   (even without being suspect) and costs for additional invasion of
   privacy\surveillance is negligible. Meaning a single person that
   doesn't do his/her job can ruin the world (in many scenario's). Looking
   at Snowden there is not the kind of security procedures to prevent it,
   either.
   So. Are the NSA guys good guys? Well. They're the enemy of the people,
   as they invade their privacy and therewith their safety. If you can be
   blackmailed, studied, influenced, etc. you are weak and vulnerable.
   Preaching to the choir, I guess. So I cannot call them good guys by a
   very long shot.
   Are the NSA guys bad guys? Well, they do anything to protect their
   nation from whatever attack could happen (bad for non-US; me). They
   steal secrets for their government (bad for non-US; me). They assist
   foreign secret agencies in subverting or avoiding legal restrictions
   put in place to protect citizens as (real/wise/elected) politicians see
   fit. (very bad for non-US; me)
   Uh. Yeah. I guess they're the bad guys. I usually feel like they are
   soldiers on a certain mission, and so no blame comes to them. But I
   feel more strongly that the organization is build to produce
   law-breaking, privacy-destroying, unethical, unfriendly, aggressive,
   anticompetative, distracting and confusing and ultimately just
   mean practices.
   So yes: the NSA is EVIL to the maximum realistic extend.
   The NSA's people enjoy a margin of appreciation. They're doing a job.
   They have their reasons. But I do believe most of them are keenly aware
   of the extremely large quantity of thoroughly unethical things their
   organization is doing, and must be considered at least partially
   responsible.