lots more info here
Former U.S. military officials told The American Report that the foreign surveillance system known as “The Hammer,” built by CIA contractor-turned whistleblower Dennis L. Montgomery, saved the lives of U.S. troops engaged in the War on Terror. “THE HAMMER” kept Americans safe after 9/11, according to those military sources.
Those sources further stated that “THE HAMMER” was a foreign surveillance tool with multiple echelons of safeguards and sign-offs that logged the identities of all U.S. personnel who accessed the super-surveillance system, up to and including the President. Those safeguards were put in place to ensure that “THE HAMMER” was never misused and turned into a domestic surveillance system to spy on the American people, obliterating their Fourth Amendment constitutional rights.
In February 2009, under newly-elected President Barack Obama, John Brennan and James Clapper commandeered and repurposed “THE HAMMER” by expanding and transforming it from a foreign surveillance system into a private, parallel platform domestic surveillance system. That system was illegal.
Brennan and Clapper moved “THE HAMMER” to a new secret location less than twenty miles from the Obama White House, where they scaled it up and covertly operated it to spy on all of America.
https://theamericanreport.org/2019/09/27/the-real-whistleblower-story-dennis-montgomery-the-hammer-the-hard-drives-the-wiretapping-of-trump-and-the-prosecution-of-general-flynn/