In early June, The Guardian had revealed that the NSA collects telephone records of millions of Verizon’s US customers under a top-secret order issued on April 25 by the secret Foreign Intelligence Surveillance Court (FISA) to the Federal Bureau of Investigation (FBI).

Those documents depict how XKeyscore allows NSA analysts to search, with no prior authorization, through vast databases of emails, online chats and browsing histories of millions of individuals. The Guardian once again turned to documents revealed by whistleblower Edward Snowden to detail XKeyscore. On that same day, senior US intelligence officials testified to the Senate judiciary committee amidst the raging debate over mass surveillance. The NSA’s training materials boast about XKeyscore being its “widest-reaching” system for squeezing intelligence from the internet, The Guardian reported on Wednesday. In fact, according to newly revealed documents given to The Guardian by Edward Snowden, one program, called XKeyscore, enables the National Security Agency (NSA) to see “nearly everything a user does on the internet”. The only thing US surveillance needs to read your private Facebook chat or private messages is your user name and a date range. The only thing US surveillance needs to read the contents of your email, with no prior authorization whatsoever, is your email address.

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