Too late with respect to Andrew McCabe. His own clearance went bye-bye when the DOJ fired him a few months back.
As for the rest, if you’re thinking, “Why do they have security clearances in the first place right now?”, good question. You would think a government famous for secrecy would move quickly to revoke access to sensitive information once former officials end their public service. (Look how hard it was for some top White House aides, most notably Jared Kushner, to get a clearance to begin with.) The answer, I think, lies in this Weekly Standard piece published last year when righties were in an uproar over H.R. McMaster allowing Susan Rice to retain her own clearance. Why would he do that? Well…
Revoking Rice’s clearance would have been unusual. And that practice applies not just to national security advisers but to other departments and agencies, such as secretary of State. The reason, the official said, is for the purposes of continuity. Without a continued security clearance, it would be illegal for government officials to discuss relevant sensitive information with a former official. The process for reauthorizing a past official’s security clearance is lengthy.
This may or may not be a bad practice, but one thing the official stressed to me was that this security clearance doesn’t give former officials like Rice continued asking privileges for sensitive information.
The real worry in letting an outspoken political enemy like Brennan keep his clearance is the prospect of him accessing new intelligence and trying to use it against Trump — but per the Standard, Brennan doesn’t get to access that intelligence. His clearance simply lets him confer with current officials in case they need to know more about something that happened when he was in government.
If it’s true that the clearances for Comey et al. are purely retrospective, with no access to new intelligence, then it’s hard to see revoking those clearances as anything but retaliation. Sanders claims in the clip below that Comey, Clapper, and the rest are “monetizing” their clearances but that’s not strictly true: What they’re monetizing is the positions they used to hold in government. Comey will be a former director of the FBI for the rest of his life. That’s why he’s landing speaking gigs, not because he still has a clearance. And needless to say, the fact that you hold a clearance doesn’t entitle you to disclose classified information publicly. That’s a crime under any circumstance. If Trump thinks Brennan is guilty of it, the DOJ should be on the case. Prosecute and then lock! him! up! No need to mess around with clearances.
In fact, in Comey’s case there’s no security clearance to revoke:
He even recently declined a temporary clearance from the IG to read the classified annex to the IG’s recent report. He didn’t want to see any classified material lest the president accuse him of leaking it. 2/2
— Benjamin Wittes (@benjaminwittes) July 23, 2018
The whole clearance thing is just retaliation for political criticism. It’s not going to get Brennan or anyone else to stop and it’s apparently not going to hurt anyone except members of Trump’s own administration, in case they need to chat with Clapper or Rice or whoever about something classified that happened under Obama and suddenly find that they’re no longer legally allowed. It’ll also set a precedent that’ll be cited when a future Democratic president wants to punish Republican natsec officials against whom he or she holds a grudge. If there’s probable cause to believe any of the Obama officials mentioned in the headline are leaking then arrest them, for cripes sake. If not, just accept that they’re going to say hysterical things like accusing Trump of “treason” and there’s nothing that can be done about it. Two clips here, one of Sanders (via the Free Beacon) and the other of Clapper alleging retribution.