Meaning: there’s what Snowden himself revealed by releasing secrets and talking to the press. But beyond this, there is what he set in motion by taking that action. Congress and other governments begin talking in public about things they had previously kept hidden. Companies have to explain some of their dealings with the state. Journalists who were not a party to the transaction with Snowden start digging and adding background. Debates spring to life that had been necessary but missing before the leaks. The result is that we know much more about the surveillance state than we did before. Some of the opacity around it lifts. This is the Snowden effect.
It is good for public knowledge. And public knowledge is supposed to be what a free press and open debate are all about.
Jay has a number of links and examples. Here’s a more recent one:
A former federal judge who granted government surveillance requests has broken ranks to criticise the system of secret courts as unfit for purpose in the wake of recent revelations by NSA whistleblower Edward Snowden. […]
But he says he was shocked to hear of recent changes to allow more sweeping authorisations of programmes such as the gathering of US phone records, and called for a reform of the system to allow counter-arguments to be heard.
Rosen’s whole piece is worth a read, by the way, because it has a smart discussion of why the Snowden saga is an important part of the story but by no means the whole story.