The country is incredibly polarized and its a negative thing for the USA. As a world leader and he is one, the responsible thing would be for him to be (at least publicly) moderate on the topic, and he happens to be right, we need the debate to figure out several very important issues about our democracy and what are the real threats to it.
As far as tactics, civil disobedience (ala MLK or Gandhi) is definitely the way to go. As a tactic, it let's you get the moral high-ground. That is incredibly powerful. Throwing a brick through a window (or releasing state secrets), doesn't get you that, even if its justified. So I would agree with Gates, Snowden could have used a better tactic. Although, how do you get attention to the issue through the noise and lies of the media without doing something drastic. I don't know. It's a tough issue.