The Obama-era FISA warrant obtained to monitor the communications of Carter Page was most likely utilized as a gateway to spy on the rest of Donald Trump’s 2016 presidential campaign, contended William Binney, a former highly placed NSA official turned whistleblower.

The same warrant against Page technically could also have been used to legally justify collecting data on the Republican National Committee (RNC) or the leadership of the Republican Party, Binney said.

Binney was an architect of the NSA’s surveillance program. He became a famed whistleblower when he resigned on October 31, 2001 after spending more than 30 years with the agency.

He was speaking during an interview that aired Sunday on this reporter’s weekend talk radio show, “Aaron Klein Investigative Radio,” broadcast on New York’s AM 970 The Answer and NewsTalk 990 AM in Philadelphia.

Binney referred to measures put into place by President Obama in January 2014 that restrict the NSA to collecting data on individuals that are only two steps removed from a target being monitored. He explained that if Page had called anyone from the Trump campaign or the RNC, the NSA could legally have spied not only on that second individual but on others called by the second person.

Stated Binney: “If you get a warrant on say Carter Page and for example he has a call or an email to the Republican National Committee or anybody in the Trump campaign, that warrant then allows them to go out two degrees from the RNC to everybody associated with the RNC and from anyone from the Trump campaign to anyone they are associated with.”

“So effectively what that means is that they had the ability to basically spy on anybody,” he said. “They could spy on everybody on the Republican National Committee or everybody in the Trump campaign.”

“Not only could they collect all the data on that second person but all of the data content as well as metadata on anybody that he talks to,” Binney added.

Contrary to Binney’s characterization that “data content” could be collected, Foreign Intelligence Surveillance Court orders do not allow the NSA to collect the contents of communications. Instead, the NSA receives so-called call record details, or CDRs, which contain information such as the date, time, and duration of calls but do not include the content of any calls.

Additionally, such warrants do not allow the collection of data on “anybody” called by the target. Numerous restrictions are placed on the NSA in accordance with applicable guidelines.

In late October 2016, then-FBI director James Comey signed the first of three successful FISA applications to obtain warrants to spy on Page, the American financial consultant who was tangentially associated with the campaign as an adviser. The second and third were renewal applications since a FISA warrant must be renewed every 90 days.

All three applications reportedly cited as key evidence against Page the largely-discredited dossier produced by the controversial Fusion GPS firm which was paid for its anti-Trump work by Hillary Clinton’s 2016 campaign and the Democratic National Committee via the Perkins Coie law firm.

According to Republican House characterizations, the FISA applications signed by Comey withheld key information raising questions about the dossier, including that it was financed by Clinton and the DNC and had known credibility issues.

Binney argued that the warrant on Page was likely used to “legitimize” and “justify” spying on the entire Trump campaign. “That’s why they want to hide the FISA request and all of the justification and affidavits that they filed to obtain it.”

Editor’s note: This post has been updated to reflect NSA data collection practices as they relate to Foreign Intelligence Surveillance Court warrants.

Aaron Klein is Breitbart’s Jerusalem bureau chief and senior investigative reporter. He is a New York Times bestselling author and hosts the popular weekend talk radio program, “Aaron Klein Investigative Radio.” Follow him on Twitter @AaronKleinShow. Follow him on Facebook.