My colleague Alex Abdo has published a nice op-ed in the Guardian this morning on the NSA's dragnet data collection programs, and the Amash Amendment that is currently being considered by the house to curb it. Alex reaches to the heart of the NSA's argument:
The NSA argues that its collection of every American's phone records is constitutional because the agency stores the records in a lockbox and looks at the records only if and when it has a reason to search them. In other words, it claims that the constitution is not concerned with the acquisition of our sensitive data, only with the later searching of it.
This is an extremely dangerous argument. For two centuries, American courts have taken the view that the constitution is concerned with the government's initial intrusion upon privacy, and not only with the later uses to which the government puts the information it has collected. That's why it is unconstitutional for the government, without a warrant, to seize your journal even if it never reads it; to record your phone call even if it never listens to it; or to videotape your bedroom activities even if it never presses play.
Alex also points out that if accepted, there is no limit to the data collection this argument could justify. (See also this post on that point.)