Frankly, Snowden is a Whistle-Blower by all definitions of the meaning. The US has some basic Whistle-Blower protections in place, which strongly motivates the government to flat-out deny any possible hint of it. Instead, the government has a large incentive to paint Snowden as a traitor, even if all evidence speaks to the contrary (nobody died from his leaks, nobody was in danger, it revealed capabilities all governments of the world already suspected and likely were attempting to guard against, he did not profit from it, he suffered at great personal detriment from the exposure, etc...)

John Oliver made a humorous analogy during his brief interview with Snowden.

When John Oliver framed the government domestic surveillance program as having the capability to intercept, store, and review your nude images (being sent to your partner, for example), it really made people upset.

However, when he framed it as being able to siphon all communications en masse, people essentially got the glazed-over look and stopped caring.

When presented with the fact that all that "nude image grabbery" and violations of personal privacy and freedoms has only resulted in a single "terrorist plot" being thwarted (that guy who gave money to a terrorist group and was promptly arrested)... people get very upset because the result certainly does not justify the cost.

It comes down to an understanding issue (or lack-thereof). Technical details bore most people, which makes them not care.

Another good analogy is the German Secret Police steaming open all letters, reviewing the contents, then re-sealing them and putting back into the mail stream. People think that's egregious, and that it would never happen in the US. But it clearly is...

These are certainly issues that majority of Americans are going to deeply care about - the trouble we have is how to communicate it in such a way as-to boil down and condense years of technical understanding in just a few words.