https://theconservativetreehouse.com/2019/05/28/the-secret-research-project-an-irs-list-an-nsa-database-and-resulting-files-on-americans/
In March 2012 the Obama administration through Attorney General Eric Holder made changes to the exploitation of intelligence databases as noted in this Wall Street Journal article later in the year:
(December 2012 – WSJ) Top U.S. intelligence officials gathered in the White House Situation Room in March to debate a controversial proposal. Counterterrorism officials wanted to create a government dragnet, sweeping up millions of records about U.S. citizens—even people suspected of no crime
A week later, the attorney general signed the changes into effect.
The 2012 changes, instituted by Eric Holder, permitted files of specific Americans to be generated under the auspices of potential terror threats. The NSA databases could be exploited by the National Counterterrorism Center to extract content that would be contained within these files on targeted Americans.
Keep in mind this is early 2012, John Brennan is Deputy National Security Advisor and Asst. to President Obama for Homeland Security.
When Attorney General Eric Holder empowered the National Counterterrorism Center with this new authority, the office assigned to the data-collection was the Terrorist Threat Integration Center (TTIC). The founder of the TTIC was John Brennan:
https://www.theatlantic.com/politics/archive/2013/05/why-eric-holders-excuse-for-spying-on-reporters-isnt-enough/275866/
Eric Holder's tenure as Attorney General is beset with failures, even if you judge him by his own goals. The fact that his Justice Department spied on AP reporters, snooping into their telephone calls, appears to be the latest betrayal of the ethos he championed prior to his time in government
https://townhall.com/tipsheet/cortneyobrien/2019/01/10/sharyl-atkisson-previews-her-case-against-eric-holders-doj-n2538618
Former CBS News reporter Sharyl Attkisson is preparing for her oral arguments in her case against the Department of Justice and the FBI. Attkisson claims her computer was compromised by DOJ agents in late 2012 while she was reporting on the Benghazi attacks, Fast and Furious and Obamacare. She first sued the Obama administration over the unwanted surveillance in January 2015.
https://www.businessinsider.com/eric-holder-germany-nsa-scandal-2014-5
US Attorney General Eric Holder will travel to Germany to discuss privacy concerns after the NSA spying scandal damaged relations between the two allies, Germany said Wednesday.
German interior minister Thomas de Maiziere told journalists in Washington that Holder has accepted an invitation from Berlin to explain how the US would curb spying on foreign nationals overseas.
Obama, Holder and Brennan have been spying for a long time. Did this abuse set Snowden off ? Most spying was done on Americans