In a discussion about the legitimacy of the government's pursuit of Snowden you point out that it has a very reasonable interest in parts (a) and (b).

But if recent whistleblower prosecutions are a guide, it quite obviously has a strong interest in part (c) -- to scare the living daylights out of anyone in their ranks who might even think of crossing them through whistleblowing.

You would agree that Snowden's ability to inspire future whistleblowers is a powerful way in which he isn't harmless to the USG? You might sincerely disagree with those who believe that this motive for getting him is at least as strong as the others. But this motive cuts into the legitimacy of the pursuit, and it should be part of your survey of the government's interests.