Much of the NSA’s ability to conduct internet surveillance has relied on AT&T being willing to assist the clandestine agency conduct these operations:

While it has been long known that American telecommunications companies worked closely with the spy agency, newly disclosed N.S.A. documents show that the relationship with AT&T has been considered unique and especially productive. One document described it as “highly collaborative,” while another lauded the company’s “extreme willingness to help.”

AT&T’s cooperation has involved a broad range of classified activities, according to the documents, which date from 2003 to 2013. AT&T has given the N.S.A. access, through several methods covered under different legal rules, to billions of emails as they have flowed across its domestic networks. It provided technical assistance in carrying out a secret court order permitting the wiretapping of all Internet communications at the United Nations headquarters, a customer of AT&T.

This really should come as no surprise. In 2006, Mark Klein, an AT&T technician, blew the whistle on the company’s involvement with the NSA in internet spying.

Fairview is one of its oldest programs. It began in 1985, the year after antitrust regulators broke up the Ma Bell telephone monopoly and its long-distance division became AT&T Communications. An analysis of the Fairview documents by The Times and ProPublica reveals a constellation of evidence that points to AT&T as that program’s partner. Several former intelligence officials confirmed that finding.

A Fairview fiber-optic cable, damaged in the 2011 earthquake in Japan, was repaired on the same date as a Japanese-American cable operated by AT&T. Fairview documents use technical jargon specific to AT&T. And in 2012, the Fairview program carried out the court order for surveillance on the Internet line, which AT&T provides, serving the United Nations headquarters. (N.S.A. spying on United Nations diplomats has previously been reported, but not the court order or AT&T’s involvement. In October 2013, the United States told the United Nations that it would not monitor its communications.)

The documents also show that another program, code-named Stormbrew, has included Verizon and the former MCI, which Verizon purchased in 2006. One describes a Stormbrew cable landing that is identifiable as one that Verizon operates. Another names a contact person whose LinkedIn profile says he is a longtime Verizon employee with a top-secret clearance.

After the terrorist attacks of Sept. 11, 2001, AT&T and MCI were instrumental in the Bush administration’s warrantless wiretapping programs, according to a draft report by the N.S.A.’s inspector general. The report, disclosed by Mr. Snowden and previously published by The Guardian, does not identify the companies by name but describes their market share in numbers that correspond to those two businesses, according to Federal Communications Commission reports.

The entire article is a fascinating, enlightening, yet not at all surprising read.