President Donald Trump tweeted Monday morning that those former intelligence officials who had emerged publicly to defend former Central Intelligence Agency (CIA) director John Brennan had done so to protect their economic interests.

Trump drew attention to the fact that holding high-level security clearance is often a prerequisite for the top jobs in Washington, DC, and that retaining that clearance after retirement — when it is no longer needed for public purposes — is a well-known perk of life at the top of the food chain in the Beltway “swamp.”

Trump began by responding to Brennan’s threat hat he might sue the president after Trump revoked his clearance last week. Brennan has described that decision as an attempt to stifle freedom of speech, and criticism of the president in particular.

But Trump said he would welcome a lawsuit as a chance to use discovery to uncover Brennan’s involvement in allegedly conducting surveillance on his campaign during the 2016 election, which led indirectly to the investigation by Special Counsel Robert Mueller:

I hope John Brennan, the worst CIA Director in our country’s history, brings a lawsuit. It will then be very easy to get all of his records, texts, emails and documents to show not only the poor job he did, but how he was involved with the Mueller Rigged Witch Hunt. He won’t sue! — Donald J. Trump (@realDonaldTrump) August 20, 2018

Trump then followed up by calling out the practice of using security clearance for economic gain:

Everybody wants to keep their Security Clearance, it’s worth great prestige and big dollars, even board seats, and that is why certain people are coming forward to protect Brennan. It certainly isn’t because of the good job he did! He is a political “hack.” — Donald J. Trump (@realDonaldTrump) August 20, 2018

Trump’s argument about corrupt relationships at the top levels of intelligence and Beltway companies is bolstered by a new book by Seamus Bruner of the Government Accountability Institute: Compromised: How Money and Politics Drive FBI Corruption.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He is a winner of the 2018 Robert Novak Journalism Alumni Fellowship. He is also the co-author of How Trump Won: The Inside Story of a Revolution, which is available from Regnery. Follow him on Twitter at @joelpollak.