A review of the claims shows that either ordinary law enforcement actions uncovered the planned attacks, or that there never was a planned attack, there never was an attack:

This suspect, in turn, was in contact with an individual in the United States named Khalid Ouazzani. Thus warned, the FBI investigated Mr. Ouazzani through traditional law enforcement methods, and discovered a burgeoning plot to bomb the NYSE.

“Ouazzani had been providing information and support to this plot,” FBI Deputy Director Sean Joyce told lawmakers.
However, Mr. Ouazzani pleaded guilty to providing material support – in his case, money – to Al Qaeda, not to terror planning. His May 2010 plea agreement makes no mention of anything related to the New York Stock Exchange, or any bomb plot, notes David Kravets in Wired magazine.

Plus, Ouazzani’s defense attorney said Tuesday the stock market allegation was news to him.

“Khalid Ouazzani was not involved in any plot to bomb the New York Stock Exchange,” attorney Robin Fowler told Wired.

As to the New York subway plot, it was discovered not by analysis of vast amounts of Internet data of foreign users, but rather by old-fashioned police work, according to The Guardian, the British newspaper that first published a secret NSA document showing the agency collected phone metadata from Verizon Business Services.
A British intelligence investigation into a suspected terrorist cell in England’s northwest first turned up a crucial e-mail address of a Pakistani extremist, write The Guardian’s Ed Pilkington and Nicholas Watt. They passed this address to the US.

Surveillance of this one address led the US to Najibullah Zazi, an Afghan-American living in Colorado who had asked the Pakistani extremist for explosives recipes. FBI agents followed Mr. Zazi as he traveled to New York. Search warrants turned up bomb components, and in 2010 Zazi confessed to a plot to bomb the city’s subway system with backpacks.

The NSA’s sweeping data interception capability “played a relatively minor role” in breaking this case, write Mr. Pilkington and Mr. Watt.

And the Guardian now hsa published the secret standards used by the NSA, and it appears we have another lie, because the standards do allow for emails to be read and phone calls to be listened to:(see here and here for the docs)

The Guardian is publishing in full two documents submitted to the secret Foreign Intelligence Surveillance Court (known as the Fisa court), signed by Attorney General Eric Holder and stamped 29 July 2009. They detail the procedures the NSA is required to follow to target “non-US persons” under its foreign intelligence powers and what the agency does to minimize data collected on US citizens and residents in the course of that surveillance.

The documents show that even under authorities governing the collection of foreign intelligence from foreign targets, US communications can still be collected, retained and used.

………
The top secret documents published today detail the circumstances in which data collected on US persons under the foreign intelligence authority must be destroyed, extensive steps analysts must take to try to check targets are outside the US, and reveals how US call records are used to help remove US citizens and residents from data collection.

However, alongside those provisions, the Fisa court-approved policies allow the NSA to:

• Keep data that could potentially contain details of US persons for up to five years;
• Retain and make use of “inadvertently acquired” domestic communications if they contain usable intelligence, information on criminal activity, threat of harm to people or property, are encrypted, or are believed to contain any information relevant to cybersecurity;
• Preserve “foreign intelligence information” contained within attorney-client communications;
• Access the content of communications gathered from “U.S. based machine[s]” or phone numbers in order to establish if targets are located in the US, for the purposes of ceasing further surveillance.

………

The documents also show that discretion as to who is actually targeted under the NSA’s foreign surveillance powers lies directly with its own analysts, without recourse to courts or superiors – though a percentage of targeting decisions are reviewed by internal audit teams on a regular basis.

………

Those procedures state that the “NSA determines whether a person is a non-United States person reasonably believed to be outside the United States in light of the totality of the circumstances based on the information available with respect to that person, including information concerning the communications facility or facilities used by that person”.

It includes information that the NSA analyst uses to make this determination – including IP addresses, statements made by the potential target, and other information in the NSA databases, which can include public information and data collected by other agencies.

Where the NSA has no specific information on a person’s location, analysts are free to presume they are overseas, the document continues.

“In the absence of specific information regarding whether a target is a United States person,” it states “a person reasonably believed to be located outside the United States or whose location is not known will be presumed to be a non-United States person unless such person can be positively identified as a United States person.”

If it later appears that a target is in fact located in the US, analysts are permitted to look at the content of messages, or listen to phone calls, to establish if this is indeed the case.

Referring to steps taken to prevent intentional collection of telephone content of those inside the US, the document states: “NSA analysts may analyze content for indications that a foreign target has entered or intends to enter the United States. Such content analysis will be conducted according to analytic and intelligence requirements and priorities.“

(emphasis mine)

Translated from the bureaucratese, this is unlimited ability to record phone calls and emails, until it is proven that they are not in the United States, and even then, the data is retained.

All that the analyst has to do is to claim that you are “not sure” if the target is a “US Person”, and it’s no harm no foul for intercepting the contents of their communications.

As Glenn Greenwald notes, this is yet more evidence that FISA court oversight is a complete joke.

H/t to Washington’s blog for the links on the NSA false claims.