Overseas Surveillance in an Interconnected World
"...there has been relatively little public or congressional debate within the United States about the NSA's overseas surveillance operations, which are governed primarily by Executive Order (EO) 12333 - a presidential directive issued by Ronald Reagan in 1981 and revised by subsequent administrations. These activities, which involve the collection of communications content and metadata alike, constitute the majority of the NSA's surveillance operations, yet they have largely escaped public scrutiny.
There are several reasons why EO 12333 and the programs that operate under its aegis have gone largely unnoticed. One is the misconception that overseas surveillance presents little privacy risk to Americans. Another is the scant information in the public domain about how EO 12333 actually operates. Finally, the few regulations that are public create a confusing and sometimes internally inconsistent thicket of guidelines."