OK, let's look at the slide that WaPo just posted (classified picture warning)

[leveymg]

58. You're missing a set of important steps and pieces here that make a mash of your hypothesis:

1) The PRISM Tasking Process flowchart describes an NSA profiling process that does not involve the FBI at any level until the very end, when the FBI ESCU determines the suspect is or is not a US person.
2) The first step in the PRISM process is conducted by software that searches a series of interlinked databases and assembles a predictive profile. The scoring on that profile determines the subject as a potential target. Bill Binney describes that profiling process here: http://civic.mit.edu/blog/schock/the-government-is-profiling-you-william-binney-former-nsa
3) Until the FBI determines that the subject is a US person, the subject is presumed to be a non-US person, and the profiling part of the system affords no 4th Amendment protections in the warrantless search of an array of databases, including those of other US and foreign intelligence services.
4) During this tasking (profiling) stage, the analyst also has access to a near real-time take of the subject's internet activities and chat. No warrant is required for the analyst to carry out this human component of the profiling process. That is described at greater length here: http://www.democraticunderground.com/10023134820
5) The analyst has 72 hours to search across NSA and outside agency databases, as well as real-time monitoring, from the time an anticulable suspicion is raised. During that investigation, supervision is minimal, and the analyst does not have to seek additional permission or a warrant. This initial profiling step is probably the unsupervised analyst's activities that Snowden was describing.

Those facts that may have been unknown or underappreciated by you, and you may want to reconsider your harsh conclusion:

There is no situation where a single analyst can just look at whatever the hell he wants. Snowden was lying about that. What's more, the NSA isn't doing any of the gathering itself.