Why are we allowing people to go around society being this ignorant of what's going on?
Take the opportunity to gently inform the guy of all the information the government has on him.
Pew, 2015
https://www.pewresearch.org/internet/2015/05/20/americans-at...
Unfortunately time-series data on perceptions and sentiments is difficult to find. But the very fact we're discussing this on the grounds of it being or not being an Edward Snowden-related awareness speaks to Snowden's impact. As does the the fact that the matter hasn't been considered notable enough to warrant tracking over time as part of a sentiment study.
Writing as someone who has been long aware of the issue, well before Snowden. But who has also noted that the nature and tenor of discussions with others since has changed markedly.