We already knew the NSA has potential access to most of the Internetting Americans do through PRISM and other programs, but the latest Edward Snowden leak reveals just how easy it is for the government to access and analyze a whole lot of information. Through a program called XKeyscore, analysts can easily sift through what the NSA calls "nearly everything a typical user does on the internet," per more documents and slides revealed to The Guardian's Glenn Greenwald. "The quantity of communications accessible through programs such as XKeyscore is staggeringly large," he adds.

And analyzing all of it is incredibly easy, too. With a simple e-mail query or selection from a pull-down menu, for example, the database can pull up more than just metadata, including the contents of a message. An analyst just has to fill out this form with a "query name" and a "justification":

Despite the field for a justification, the "request is not reviewed by a court or any NSA personnel before it is processed," says Greenwald. Then, this next screen pops up and "the analyst then selects which of those returned emails they want to read by opening them in NSA reading software," explains Greenwald.

Further slides reveal that the NSA can do this with all sorts of other communications, like Facebook chat, and presumably the other tech companies the government works with, like Microsoft, which owns Skype:

For these other communications, the NSA doesn't even need an e-mail address, but can search using other keywords and queries. 

As with all of these leaks, the NSA alleges that it only uses these systems for "legitimate foreign intelligence targets," the agency said in a statement to The Guardian. If the NSA wants to surveil Americans it needs FISA court permission — unless, of course, those people have ever had contact with one of these "legitimate foreign intelligence targets" or "two or three hops" from those people. "The government inevitably sweeps up the communications of many Americans," said the ACLU's deputy legal director, Jameel Jaffer.

Legal or not, it's technically very easy for the government to do. Snowden said he could "wiretap anyone, from you or your accountant, to a federal judge or even the president, if I had a personal email." And despite that little "justification" box, his searches were rarely questioned, he said. "Even when we are, it's usually along the lines of: 'let's bulk up the justification.'"