Well, them reading this data is a known fact, mostly from Snowden's leaks. Blackmail happening is harder to prove, but it would approach incompetence if the NS

Well, them reading this data is a known fact, mostly from Snowden's leaks. Blackmail happening is harder to prove, but it would approach incompetence if the NSA at least found no opportunity to blackmail someone using the data we know they have access to.