Any sitting US President reserves the right to revoke an (former) agents security clearance. Here's a blast from the past:
"1) In 2011, Brennan, then the country’s chief counterterrorism adviser, had sworn to Congress that scores of drones strikes abroad had
not killed a single noncombatant — at a time when both the president and the CIA were both receiving numerous reports of civilian collateral deaths.
2) In 2014, John Brennan, now as CIA director, lied emphatically that the CIA had not illegally accessed the computers of U.S. Senate staffers who were then exploring a CIA role in torturing detainees. Or as he told Andrea Mitchell: “As far as the allegations of the CIA hacking into Senate computers, nothing could be further from the truth. . . . We wouldn’t do that. I mean, that’s just beyond the, you know, the scope of reason in terms of what we do.” Brennan’s chronic deceptions drew the ire of a number of liberal senators, some of whom echoed the
Washington Post’s call for his immediate resignation. After months of prevarications, but only upon release of the CIA inspector general’s report, Brennan apologized to the senators he had deceived.
3) Brennan, in May 2017, as an ex-CIA director, again almost certainly did not tell the truth to Congress when he testified in answer to Representative Trey Gowdy’s questions that he neither knew who had commissioned the Steele dossier nor had the CIA relied on its contents for any action. Yet both the retired National Security Agency director, Michael Rogers, and the former director of National Intelligence, James Clapper, have conceded that the Steele dossier — along with the knowledge that it was a Clinton-campaign-funded product — most certainly
did help shape the Obama’s intelligence communality interagency assessments and actions, often under the urging of Brennan himself. There are also numerous reports that, despite his denials about knowledge of the dossier, Brennan served as a stealthy conduit to ensure that it was disseminated widely, at least in the sense of meeting in August 2016 with Senator Harry Reid to brief the senator about its unverified contents in hopes that he would pressure the FBI to further its investigations, which Reid did in a call two days later to James Comey."
source
So Brennan is now a persecuted superstar in the media limelight is he? Another victim of the Trump administration? Revoking his security clearance is long overdue, and I hope several others get the same treatment.