That's the allegation contained in a class action lawsuit, and it was reported by no less than the New York Times in 2007.  Business Insider noted this and other troubling information on the possible magnitude of NSA spying on Americans.

Over the weekend James Risen and Eric Lichtblau of The New York Times - who won a Pulitzer Prize in 2005 for this story on the NSA gaining the cooperation of U.S. telecommunications companies to obtain backdoor access to customer data - mentioned a detail from 2007 (emphasis ours):

In Virginia, a telecommunications consultant reported, Verizon had set up a dedicated fiber-optic line running from New Jersey to Quantico, Va., home to a large military base, allowing government officials to gain access to all communications flowing through the carrier's operations center.  (snip)

The news about the Verizon-NSA fiber optic connection came from a class action lawsuit brought by a former AT&T engineer who worked on a proposal to give the the NSA access to all the global phone and email traffic that ran through an AT&T network center in Bedminster, N.J.

The Israeli hardware, which can record data that comes through an internet protocol network, was discovered by a former AT&T engineer named Mark Klein and confirmed by former NSA senior executive Thomas Drake.

Another former NSA employee named William Binney, who, like Snowden, believes the NSA's surveillance has gone too far, says that ever since 9/11 the NSA has been hoarding electronic data - phone calls, GPS information, emails, social media, banking and travel records, entire government databases - and analyzes, in real time, "all of the attributes that any individual has" in addition to making networks of connections between individuals.

Binney, one of the best mathematicians and code breakers in NSA history, quit after 32 years in late 2001 because, in his view, he "could not stay after the NSA began purposefully violating the Constitution."

The American public has been treated to pious denials of cooperation by major internet and telecom providers that look to be misleading, which can only fan the flames of public suspicion that something really, really bad has been going on.

President Obama famously declared that his forces must bring guns to knife fights in order to win. Is spying on Americans part of his firearms arsenal?