[14][15] The NSA, alongside the CIA, maintains a physical presence in many countries across the globe; the CIA/NSA joint Special Collection Service (a highly classified intelligence team) inserts eavesdropping devices in high-value targets (such as presidential palaces or embassies).

The NSA's actions have been a matter of political controversy on several occasions, including its role in providing intelligence during the Gulf of Tonkin incident, which contributed to the escalation of U.S. involvement in the Vietnam War.

[33] A secret operation, code-named "MINARET", was set up by the NSA to monitor the phone communications of Senators Frank Church and Howard Baker, as well as key leaders of the civil rights movement, including Martin Luther King Jr., and prominent U.S. journalists and athletes who criticized the Vietnam War.

[55] According to a 2010 article in The Washington Post, "every day, collection systems at the National Security Agency intercept and store 1.7  billion e-mails, phone calls and other types of communications.

"[56] Because of its listening task, NSA/CSS has been heavily involved in cryptanalytic research, continuing the work of predecessor agencies which had broken many World War II codes and ciphers (see, for instance, Purple, Venona project, and JN-25).

[63] Investigative journalist Duncan Campbell reported in 1988 on the "ECHELON" surveillance program, an extension of the UKUSA Agreement on global signals intelligence SIGINT, and detailed how the eavesdropping operations worked.

[64] On November 3, 1999, the BBC reported that they had confirmation from the Australian Government of the existence of a powerful "global spying network" code-named Echelon, that could "eavesdrop on every single phone call, fax or e-mail, anywhere on the planet" with Britain and the United States as the chief protagonists.

[113] According to the Foreign Policy magazine, "... the Office of Tailored Access Operations, or TAO, has successfully penetrated Chinese computer and telecommunications systems for almost 15 years, generating some of the best and most reliable intelligence information about what is going on inside the People's Republic of China.

The reluctance of congressional houses to look into these affairs prompted a journalist to write, "If a similar series of tragic blunders occurred in any ordinary agency of Government an aroused public would insist that those responsible be officially censured, demoted, or fired."

[147] A 1983 report of the Office of Technology Assessment stated that "It appears that the NSA [National Security Agency] (and possibly CIA) use the polygraph not to determine deception or truthfulness per se, but as a technique of interrogation to encourage admissions.

The $1.5B data center is being built at Camp Williams, Utah, located 25 miles (40 km) south of Salt Lake City, and will help support the agency's National Cyber-security Initiative.

[60] Following the [194] UKUSA Agreement between the Five Eyes that cooperated on signals intelligence and ECHELON,[195] NSA stations were built at GCHQ Bude in Morwenstow, United Kingdom; Geraldton, Pine Gap and Shoal Bay, Australia; Leitrim and Ottawa, Ontario, Canada; Misawa, Japan; and Waihopai and Tangimoana,[196] New Zealand.

[220] Because of concerns that widespread use of strong cryptography would hamper government use of wiretaps, the NSA proposed the concept of key escrow in 1993 and introduced the Clipper chip that would offer stronger protection than DES but would allow access to encrypted data by authorized law enforcement officials.

Despite this, the NSA/CSS has, at times, attempted to restrict the publication of academic research into cryptography; for example, the Khufu and Khafre block ciphers were voluntarily withheld in response to an NSA request to do so.

[54] On December 16, 2005, The New York Times reported that under White House pressure and with an executive order from President George W. Bush, the National Security Agency, in an attempt to thwart terrorism, had been tapping phone calls made to persons outside the country, without obtaining warrants from the United States Foreign Intelligence Surveillance Court, a secret court created for that purpose under the Foreign Intelligence Surveillance Act (FISA).

[255] More specifically, Snowden released information that demonstrated how the United States government was gathering immense amounts of personal communications, emails, phone locations, web histories and more of American citizens without their knowledge.

As Snowden recounts, "I believe that, at this point in history, the greatest danger to our freedom and way of life comes from the reasonable fear of omniscient State powers kept in check by nothing more than policy documents...

"[257] In March 2014, Army General Martin Dempsey, Chairman of the Joint Chiefs of Staff, told the House Armed Services Committee, "The vast majority of the documents that Snowden ... exfiltrated from our highest levels of security ... had nothing to do with exposing government oversight of domestic activities.

[262] In September 2008, the Electronic Frontier Foundation (EFF) filed a class action lawsuit against the NSA and several high-ranking officials of the Bush administration,[263] charging an "illegal and unconstitutional program of dragnet communications surveillance,"[264] based on documentation provided by former AT&T technician Mark Klein.

[266]: 1568–69 In May 2008, Mark Klein, a former AT&T employee, alleged that his company had cooperated with NSA in installing Narus hardware to replace the FBI Carnivore program, to monitor network communications including traffic between U.S.

[268] A 2013 advisory group for the Obama administration, seeking to reform NSA spying programs following the revelations of documents released by Edward J. Snowden,[269] mentioned in 'Recommendation 30' on page 37, "...that the National Security Council staff should manage an interagency process to review regularly the activities of the US Government regarding attacks that exploit a previously unknown vulnerability in a computer application."

[284] As an example, NSA director General Keith B. Alexander mentioned at the annual Cybersecurity Summit in 2013, that metadata analysis of domestic phone call records after the Boston Marathon bombing helped determine that rumors of a follow-up attack in New York were baseless.

As of May 7, 2015, the United States Court of Appeals for the Second Circuit ruled that the interpretation of Section 215 of the Patriot Act was wrong and that the NSA program that has been collecting Americans' phone records in bulk is illegal.

[297] The NSA has been reported to have access to all communications made via Google, Microsoft, Facebook, Yahoo, YouTube, AOL, Skype, Apple and Paltalk,[298] and collects hundreds of millions of contact lists from personal email and instant messaging accounts each year.

[300][301] Domestically, the NSA has been proven to collect and store metadata records of phone calls,[302] including over 120 million US Verizon subscribers,[303] as well as intercept vast amounts of communications via the internet (Upstream).

[307] The Intelligence Committees of the US House and Senate exercise primary oversight over the NSA; other members of Congress have been denied access to materials and information regarding the agency and its activities.

"[312][attribution needed] The NSA has "generally disregarded the special rules for disseminating United States person information" by illegally sharing its intercepts with other law enforcement agencies.

In mid-December 2013, U.S. District Judge Richard Leon ruled that the "almost-Orwellian" program likely violates the Constitution, and wrote, "I cannot imagine a more 'indiscriminate' and 'arbitrary invasion' than this systematic and high-tech collection and retention of personal data on virtually every single citizen for purposes of querying and analyzing it without prior judicial approval.

"[318] This statement came under scrutiny months later, in June 2013, when details of the PRISM surveillance program were published, showing that "the NSA apparently can gain access to the servers of nine Internet companies for a wide range of digital data.

"[332] Former employee David Evenden, who had left the NSA to work for US defense contractor Cyperpoint at a position in the United Arab Emirates, was tasked with hacking UAE neighbor Qatar in 2015 to determine if they were funding terrorist group Muslim Brotherhood.